Nielsen/NetRatings (they carry a big website ranking stick) is changing the way they rank websites. Gone are the days of ranking by page views. Yesterday they announced that websites will now be ranked by the length of time site visitors "linger" on sites.
This movement pushes Google from 3rd place to 5th. AOL and Yahoo on the other hand, just made colossal jumps (now ranked #1 and #2 respectively).
Theoretically, Nielson's little change could adversely affect Google's online advertising presence, not to mention their overall reign of all things web.
I guess that would mean that all the clean, productive, short-term searches people do on Google don't amount to much to all the crap that AOL, Yahoo, and MSN put on their homepages. I wonder how this ranking system takes into account the fact that people leave browsers open for hours while they are preoccupied with other activities. I leave windows open for days on end.
24/7 Wall St. already called it: the new system is a bust. And Google don't care.