Quora, the Q&A site that bloggers and Silicon Valley early adopters can’t get enough of, is growing quickly, according to a new report.  Andrew Chen published some stats today showing that even a conservative estimate pegs the January growth rate at 150 percent.

A little background info: Chen’s a blogger who’s worked as both an entrepreneur-in-residence at Mohr Davidow Ventures and a director of product marketing at Revenue Science.  He’s also a big Quora fan, writing, "My prediction for Quora is that it’s going to turn into a huge, important Internet property – it’ll break out of the Valley network easily and inevitably."

As for the numbers, Chen pulled app data from both AllFacebook and AppData, and called his conclusions conservative since not everyone who visits Quora will register an account or sign in through Facebook.

So on to the stats.  The subtitle on Chen’s blog post speaks of "150% growth in January, 160k monthly actives, 18k daily actives."  Later, he added, "As you can see from the graphs, Quora is growing on a very nice clip, over 2X larger in MAU over the last month."

That’s good news for the site’s supporters.  Near-constant media attention will probably continue to feed that rise, and at this point, no serious problems (which might include spam, a decline in the quality of answers, or Twitter-like outages) have cropped up.

We’ll try to continue to keep an eye on these stats in the months ahead.