aristotle - 9:56 am on Apr 8, 2011 (gmt 0)
I agree that Google probably doesn't use bounce rate or click backs as ranking factors. But there are some other aspects of user behavior that they could use. For example, here are some possible positive signals
-- A user bookmarks a page as a favorite.
-- A user saves a copy of a page on their hard drive.
-- A user returns to the same page later.
In my opinion one of the main reasons Google created its Chrome browser was to be able to collect this type of information. I believe that they probably use it.
NOTE: When I say that Google probably uses some signals from user behavior, I'm not talking about bounce rate or click-backs. Instead, I'm talking about signals like the three that I listed above. I'm not talking about bounce rate or click backs.