It has been more than a year since we flagged Twitter as the most buzzworthy social application in Silicon Valley. Thirteen months later, the micro-blogging site, which allows users to follow each others’ short online updates, has become an indispensible tool for the online cognoscenti who have gathered at San Francisco’s Moscone Center for this year’s Web 2.0 expo.

Jenn Van Grove, a social media consultant, says Twitter helps her follow the latest online buzz and keep in touch with hard-to-reach people. “If I need to get in touch with someone, Twitter is much faster than email,” she says. 

Ryan Kuder, a former Yahoo who is working on a new web startup, assured me that time invested keeping track of contacts on Twitter returns dividends.  ”People ask if you can spend too much time on Twitter,” he says. “I say you can’t spend enough.”

Sceptical journalist that I am, I signed up for Twitter in March of last year but never really got into the service. Intrigued, I dug out my Twitter ID and passed it along to Jenn, Ryan and a few other bloggers seated at our table inside the Web 2.0 blogger lounge. I have now been Twittering for all of two hours, and thanks to my new Twitter friends, I’ve managed to attract more than 50 followers.  Better late than never, I suppose.