When offered the choice between looking for information on the Web, or looking at pictures of friends, pasting song lyrics into status messages and raising virtual produce, most people apparently choose the latter. So we can deduce from the latest Web statistics, which show Facebook officially outpacing Google as the most popular Web site in the United States this week.

The global analytics firm Hitwise announced on Monday that Facebook edged Google out for the week ending March 13, grabbing 7.07 percent of all U.S. Web traffic, compared to Google’s 7.03 percent. While still impressive, it’s worth noting that Hitwise only counts traffic to the Google.com domain. Sites like Gmail and Google Reader are not counted.

Facebook saw a 185 percent traffic boost for that week compared to the same week in 2009. The site has narrowly surpassed Google in traffic on holidays and weekends before, but last week represents the first time it has manage to keep ahead for seven straight days.

Why the boost? The runup to this week’s social-media-centric SXSW festival – which officially began on Saturday toward the end of the recording-breaking week– might have something to do with it. In the long term, so might the proliferation of large-scale Facebook games like Farmville, which now boasts 82.7 million active users – over 20 percent of all Facebook users.