The Nielsen Company today released estimates of US usage of the Internet and visits to major web destinations for January.

The numbers showed that people spent an average of more than 5 hours less on their computers in January, from 64 hours and 9 minutes in December to 58 hours and 52 minutes.

Time spent at the most popular web sites fell except at Facebook, where people spent an average of 7 hours extra.

Here is more detailed info:

Example: The data indicates that 64.6 million home and work Internet users visited at least one of the eBay-owned sites or launched an eBay-owned application during the month, and each person spent, on average, a total of 1 hour, 9 minutes and 32 seconds at one or more of their sites or applications.
The parent level is defined as a consolidation of multiple domains and URLs owned by a single company or division. The brand level is defined as a consolidation of multiple domains and URLs that has a consistent collection of branded content.