The Online Publishers Association (OPA) reports, that the (Nielsen NetRating) Internet Activity Index shows that content extends its lead (in total time spend) as the number one activity on the web.
The switch happened sometime last year and develops mainly against communication. But this is only 'natural'. The selection and amount of available content (incl. Video) has grown and more and more people looking for content online (replacing offline).
In 2003 for many eMail was the main reason to access the Internet. And don't get it wrong, the total time people spend online has grown considerable since than, including Communication.
IAI July 2007 figures (against previous month)
Content 50,9 % (+ 2,6 %)
Communication 30,4 % (- 5,0 %)
eCommerce 14,1 % (+ 2,2 %)
Search 4,6 % (+ 2,2 %)