Thanks to social networking websites such as Facebook, the time spent on internet has seen an overall increase over the past few months. For instance, the average American Facebook user now spends close to 7 hours a month just on this network site.
Here are some trends observed by Nielsen in their latest study (Jan 2010) of average US internet usage
Internet sessions per person : 55
Domains visited per person : 90
Web pages per person : 2,621
PC time per person : 58hr : 52mi : 05s
Duration of web page viewed : 56 seconds