Like kevin said it was removed in 10.1 and replaced with the Ping sidebar. It's a pretty stupid move on apple's part they should allow the user to select what they want to see.
answered Oct 02 '10 at 09:39
It was removed in 10.1 http://reviews.cnet.com/8301-13727_7-20017685-263.html
answered Oct 02 '10 at 00:52