After Nielsen/NetRatings changed its methodology to account for "total minutes" a month ago, the Googlemeister dropped from 1st to 5th, while AOL jumped from 6th to 1st in overall site "popularity."
Why the sudden shift? Nielsen considers time spent to be more reliable measure of a site's value. Sites like AOL and Yahoo rely on interactive widgets and a new programming language known as Ajax; such features allow users to stay on a single page longer, but also reduce overall page views.
AOL Time Image by Valliravindran