comScore released its Media Metrix Top 50 U.S. Web Properties report for January. Among the findings: a lot of people are spending a lot of time online.

“In January, the average U.S. Internet user spent a record 36 hours online, reflecting the growing importance of digital media to Americans’ daily lives,” said Jeff Hackett, executive vice president of comScore. “Among the biggest category gainers in this heavy month of Internet usage were Travel and Career sites, which posted double-digit gains, and of course Tax sites as the non-procrastinators among us decided to get an early jump on getting their refunds.”

So where are they spending their time?

Here’s the top 50:

Note that Facebook is below Yahoo and Microsoft sites. Google sites are on top, no doubt helped significantly by YouTube.