In the past couple weeks, Steven Groves has informed the online world that he spent a weekend camping, shopped for trees at Home Depot, saw "Pirates of the Caribbean" and worked on a presentation.

Groves is sharing the most mundane details of daily life on Twitter, which invites users to answer the question "What are you doing?" in 140 characters or fewer. Twitter members report to anyone who cares that they are "updating my blog" or "waiting to get my hair cut" or have "logged another two hours on 'Halo 3.' "

Now, critics are asking: So what?

"I don't really need to know that you're heading to the bathroom," Forrester Research analyst Charlene Li wrote recently on her blog.

But since its quiet launch about a year ago, initially as an experiment involving cell-phone text messages on the Web, Twitter has developed a following. Even Democratic presidential candidates John Edwards and Sen. Barack Obama have jumped on board. Sen. Hillary Rodham Clinton's camp said recently that her Twitter page will launch in the next few days.

"Our campaign is about empowering people, and the cutting-edge technology available today gives people across the country the opportunity to interact with us and become part of our campaign," Edwards spokeswoman Colleen Murray said.

Twitter, like online diaries before it, raises questions about just how much appetite Internet users have for insignificant information but also shows how the Web continually evolves as a medium of communication. Already there are sites that look similar to Twitter, notably France's Frazr and Germany's Wamadu. Another site, Plazes, adds to the Twitter model by not only asking people to share responses to "What are you doing?" but also to "Where are you?"

In many ways, Twitter represents the latest evolution of the always-accessible technology of the past few years. Mobile phone users are increasingly tapping out text messages, and self-expression blogs and social networking sites allow even the smallest details of life to be chronicled for the masses. Unlike blog entries and MySpace pages, Twitter is a 20-second diversion for a quick thought, rather than a 20-minute investment of time.

Tracking the course of a Twitter member's musings is not much different from subscribing to a blog, said Scott Johnston, 33, a self-described techie who blogs and Twitters from Silicon Valley. He's following the thoughts of strangers who have something interesting to say while maintaining control over whom he follows and how often.

"I read about 30 blogs a day," he said. "Imagine me trying to call those 30 people every day to try and understand how their day was. It would be quite the effort."

For now, some analysts say, Twitter is a disorganized collection of random thoughts that needs more focus if it wants to become a viable business.

"The key thing is context, not publishing to the world but to the people who care," said Li, who said she would be interested in a Twitter-like service where co-workers collaborating on a project, for example, could easily stay in touch by tapping out quick messages to the group. "The way it's constructed now, it's going to the world. Frankly, I don't have a big enough ego to think that everyone out there cares what I have to say."

Twitter's founders say their priority is to shape the product into something that will keep people engaged. Less important, for now, is how they will make money from it. The San Francisco start-up, which is bringing in no revenue, is about to close a round of venture capital funding, co-founder Biz Stone said.