Foursquare founder Dennis Crowley’s plan is to do for places and experiences, what Amazon has done for books, and Netflix has done for movies. Crowley calls Foursquare a “recommendation engine.” I called it an “anticipation engine” when I caught up with Crowley at the at this month’s 140 Characters Conference in New York City. I asked him what changes are coming that users don’t expect? Will Foursquare evolve in ways that we’re not yet imagining? Watch the 140-second interview to hear what he said.

“You want to make sure everything you tweet is accurate, honest and useful,” Curry said in an interview. “I’m held to a very high standard, and you need to meet that.”

Curry sets a high-standard each day as host of as NBC’s “Today” show, and when the cameras are off, she maintains her journalism standards when she sends updates on Twitter.

“I don’t want to let people down,” she said. “It’s a lot of responsibility.”

Two years ago at the 140 Characters Conference in New York City, Curry emerged as a social media star because she explained how seriously she approaches each tweet. That won the respect of the crowd and her Twitter following quickly grew from 40,000 to over one million. Curry’s interview with HiAnthony.com took place at last year’s #140conf, as it’s known on Twitter. She will speak again at this year’s 140 Characters Conference, which kicks off June 15 at the 92nd Street Y in Manhattan.

Twitter is changing, Curry said, comparing it to the evolution of transportation. “When have generations been able to expereince something, knowing that they’re at the ground stage of something? It’s a rare experience.”

NEW YORK — Jeff Pulver took a few minutes to discuss what to expect at this year’s 140 Characters Conference: New York City. It’s the second annual conference, referred to as #140conf on Twitter. The #140conf tag has been used every day on Twitter since the conference a year ago, Pulver said. Last year’s conference helped propel NBC News journalist Ann Curry (@AnnCurry) from 40,000 followers to over 1 jmillion and also featured Wine Library TV’s Gary Vaynerchuk (@garyvee). Both Curry and Vaynerchuk are speaking again at this year’s conference. Also speaking at the conference, on April 20 and 21 at the 92nd Street Y in New York City, Ivanka Trump (@IvankaTrump), Donny Deutsch (@Donny_Deutsch) and MC Hammer (@MCHammer).

“What we’re really looking at is the effects of the real-time Internet on both business and we the people ,” Pulver said during a recent interview at the Roger Smith Hotel (@RSHotel).

“We will be looking at the Haiti disaster,” and topics including media, fashion, music and sports. “The people define the moment,” said Pulver, who runs the conference and is also Vonage’s original founder. “It’s about serendipity. It’s about life.”

I attended last year’s 140 Characters Conference: New York City and connected with many folks there. The interaction at the conference helped me to become more active on Twitter. By the way, Pulver said, March 5 is the last day to get into the conference for $100 for both days. As of March 6, it goes up to $140 for both days. I’ll put the conference registration link here and the schedule link here, because I believe it’s well worth the investment.

How about President Barack Obama? Will he be less likely to speak his mind in public after ABC News reporters used Twitter to spread his off-the-record comment about Kanye West acting like a “jackass” on MTV’s video music awards show? TMZ.com, owned by DailyFinance’s parent company AOL, then published audio and video of those comments. Will such incidents cause celebrities and non-celebrities to be more on guard for fear that their every move may be made public via social media?

“The site is back up, but we are continuing to defend against and recover from this attack,” Twitter wrote on its status update blog after 11 AM EST. “We are defending against a denial-of-service attack.” Even so, over an hour after Twitter said that the site is back up, many folks are still unable to get it working.

As more demand is put on Twitter to keep its site running 24 hours-a-day, seven days a week, its users will become less patient, assuming Twitter had figured out a way to deal with service outages after more than three years of serving its customers. In some ways, the site could be a victim of its own success: Twitter fans may have been more forgiving of outages when the site was thought to be a club of insiders by the early adopters of its technology. As it becomes more popular, however, Twitter may be running out of such goodwill. As it grows to a hoped one billion customers by 2013, users will expect the site to be able to handle such attacks.

Mashable’s Pete Cashmore wrote that Twitter was down because it was “saturated with so many fake requests that the victim is unable to return legitimate ones. Knowing that the cause is a malicious attack does take Twitter off the hook to some degree.”

PCmag.com reported that Facebook was down briefly today at the same time as Twitter, but returned “shortly thereafter.” There were other denial-of-service attacks early this week: on Monday, sites operated by Gawker Media had problems. Allegedly, The Consumerist blog, which is hosted by Gawker Media, also had problems.

Twitter has also been dealing with spammers and technical issues. Last week, the company said some of its newer members were having trouble with their followers. Some were seeing followers dropped without any action on their part. Other Twitter account-holders were unable to have folks sign up and follow them at all.

“This includes seeing empty followers lists and zeroed follower counts,” Twitter wrote on its status blog on July 28. “We’re actively working on this problem and hope to release a fix soon.”

Twitter has not responded to requests from DailyFinance for information regarding last week’s followers problem and details about who might be responsible for today’s attack.

“We’re eager to see if encouraging a sense of wonder and discovery leads to a better first impression of Twitter,” Doug Bowman, creative director at Twitter, wrote in a Tweet and quoting from the company’s blog Tuesday. Earlier in the day, he Tweeted, “Feeling calm before the storm. Except there’s no storm. Only quietly mounting tension and anxiety for what lies ahead.” What lies ahead for Twitter is the lucrative search business.

Google (GOOG) has been raking in the loot since becoming king of search. Being even a court jester in the kingdom of search is miles away for Twitter, but real-time Twitter search has to be worth a few gold coins. And some might argue that real-time search is more relevant as cultures around the globe demand news of the moment. This makes Twitter more valuable, although it seems it’s too late for a tech giant to buy the tech upstart.

More importantly for Twitter, this step lifts the curtain for non-Twitter members to see what’s inside. What used to be a sign-up page for those who weren’t Twitter members at twitter.com now shows a real-time search page listing the most searched Twitter topics. If Google is at all worried about the colorful photos and categories at bing.com, imagine the nervousness about twitter.com’s list of hot weekly and daily topics, and those changing by the moment.

Now those menus are available to folks who go to twitter.com and they don’t have to sign up or be Twitter users to use the search feature. The downside for Twitter users is you can’t see the weekly and monthly listings of the trending topics when you are logged into your account. I’m betting that will change soon.

“Twitter has moved from simple social networking into a new kind of communication and a valuable source of timely information,” Twitter wrote on its blog on Tuesday. And in a likely unintentional nod to Google’s don’t-be-evil motto, Twitter wrote, “Also, it’s fun.”

Twitter is one-upping Google. Folks use Google constantly for search without signing up for a Google membership. Of course, Google has Gmail, Google Docs, iGoogle and other services that Web surfers may sign up for. Twitter did the opposite, which I argue is a better approach. They got millions to sign-up first, and then they opened up the no-membership-required search page. Cleverly done.

And there’s more to come, according to Twitter CEO Evan Williams. In a Tweet Tuesday evening, he thanked his search team for the new front page. “That was buggin’ me,” he wrote. “Onward.”

Hey Google, sounds like there’s more to come. Has Microsoft been distracting you? There’s a new target in town.

“The truth is, we’re not even entering acquisition talks right now because we’re absolutely committed to building value.” Stone said. This comes after co-founder Jack Dorsey told me on June 3 that Twitter would “consider” selling at the right price.

“What he [Dorsey] meant to say was, because we have investors, if there was a very serious offer, you’re irresponsible not to listen,” Stone told DailyFinance. Dorsey is a board member and he expressed what any good company board member should, Stone said, which is, “If an offer captures the perceived upside, then we have fiduciary responsibility to look at it seriously.”

According to TechCrunch, which acquired confidential Twitter documents and published some of the information contained therein last week, Twitter hopes to have one billion users by 2013. Using that as perceived upside, if a company paid $2 a user, based on Twitter hoping to generate $1 per user per year, I’m estimating a minimum $2 billion price tag. Anything less probably wouldn’t fetch the micro-blogging website at this point. Realistically, it would take a higher offer.

Yes, you can argue that Twitter’s not making money. The company appears to mulling over how to turn their growing audience into cash. Last week, Twitter launched a Twitter 101 sub-site to show users how to make money Tweeting, and Stone said the company will make money this year.

Markets, and anything of value, trade on perception. Why does gold trade at more than $900 an ounce and not less than $400 an ounce as it did just five years ago? It’s the same ounce of gold. Weighs the same. Looks the same. Liquidity hasn’t changed much since 2004. It’s about the perceived demand for the value of that ounce.

The value of an ounce of Twitter has gone up considerably since January, when it caught fire on Google Trends, or April, when there were rumors of interest from Google, Microsoft or even Apple. That growing popularity since January? That’s demand. As it grows, so does perceived value and the price it would take to buy Twitter.

What’s changed? Perception. Not much else has changed for Twitter. Same guys running the place. They’ve hired a few more employees, with 55 in all, Stone said and many more users. Whether it was Google (GOOG), Microsoft (MSFT) or Apple (AAPL), a savvy buyer should have pounced when the value was lower. Today, it’s much more. Sure, Twitter’s value could have dropped in recent months and can still drop. But if it doesn’t, they’ve missed out.

It’s too late to buy Twitter. The only companies that could afford the micro-blogger are public, though privately-held Facebook might squeak by too. If they pay too much, their shareholders will revolt. They’ll revolt even more if it takes years to make money with Twitter. As we’re seeing with Google and YouTube or News Corp. (NWS) and MySpace, shareholders get angry when saddled with sexy-named tech darlings that don’t morph into printing presses.

The question for anyone looking at Twitter is: Can they duplicate it? Sure they can. Facebook duplicated MySpace, and some would argue, improved upon it. Aye, but the danger of a tech giant thinking ‘We can come up with our own Twitter-like product at a fraction of what it would cost to buy that company,’ is this: You build it and no one cares. Oh, then you look bad. Worse than if you overpaid for Twitter and it flops. Google built Google Video, which didn’t catch on, so they bought YouTube. Now Hulu may, or may not, be a better YouTube, but at least Google can rival Hulu with YouTube. They wouldn’t be in the fight with Google Video.

Twitter has been too hot for too long for it not to matter. Why is it succeeding? That’s a story for another day. Is it succeeding? Yes. Will someone come along and beat it? Maybe. Probably. Ashton Kutcher, who has the most Twitter followers in the world, said Twitter may eventually be beaten at its own game, at the Fortune conference last week.

But what if no one beats it? What if Google Wave goes the way of Google Video? What if there are too many Twitter users, companies and others rooting for and invested in Twitter? Then the coming Twitter-killer may not be able to succeed.

I believe it’s already too late. Twitter has become a household name. Its “perceived upside,” as Stone called it, makes it too expensive for a Google, Microsoft or Apple to pay without looking like fools to their shareholders. If they dared to put forth an inflated bid, it sounds like Twitter would at least listen. A buyer faces the risk of colossal failure; or if Twitter succeeds, they’ll look like geniuses for catching lightning in a bottle.

So Google or Microsoft or Apple, you have to ask yourself — do you feel lucky?