The “metro” blogs, focus on local events, reflections, recommendations, news and complaints, “We’re kind of that friend of yours that always knows what’s happening in the city,” said Jen Chung, editor-in-chief of the New York-based Gothamist.

Many of them cover just one metropolis. But this summer, Metroblogging launched a network of blogs for major cities including Chicago, New York, San Francisco, London and Vienna.

Gothamist also expanded its base, setting up Chicagoist in June and LAist in July.

Neither Metroblogging.com nor Gothamist.com is making a profit — their owners work other full-time jobs, and their writers are unpaid.

But visit numbers are getting interesting. Gothamist, for example, averages over 30,000 visitors daily (Instapundit.com, one of the most popular blogs, attracts nearly 140,000 daily visitors.)

And because localized advertising from Google and Overture has grown substantially over the past few months, local blogs even have the potential to be profitable.

Of course, local group blogs cannot match resources like Citysearch or a newspaper’s online metro section for comprehensive restaurant reviews or concert listings.

But the individual voices of local residents may offer a level of authenticity missing elsewhere.

From CNN.