levo - 4:08 pm on Jun 26, 2012 (gmt 0)
Does Chrome track on-page user actions? Copying text/image, scrolling to the end of the page, switching back and forth with another app (like following a tutorial) etc.?
Edit: I forgot, +1 button does all the tracking, including mouse movements.
Google might be combining user's actions with bounce/exit rate to get a more representative number.