via allthingsd.com
Via All Things Digital — “Check out this engagement chart, courtesy of Citigroup’s Mark Mahaney. It’s a neat illustration of the Web 2.0 era, and does a nice job of explaining why Google is so freaked out about Facebook, and why AOL and Yahoo seem to be in eternal turnaround mode. (Note that just a couple of years ago, someone might have thought to include Myspace in here. Remember?)”