After a three month hiatus, Google has brought back Author Stats to Google Webmaster Tools.
I personally noticed it yesterday when I was playing around with my Google Webmaster Tools account.
Author stats shows you statistics for pages for which you are the verified author. So I can see stats from this site, Search Engine Land and other sites I write at where my Google Authorship is verified.
Here is a screen shot of the stats starting to accumulate again:

Just some history, this feature was initially introduced in December 2011 then went away in April 2012 and is now back in July 2012.
Forum discussion at Google+.

Comments:
Jason Kamara
07/19/2012 09:04 pm
It's in experimental testing under Labs in GWT; in case anyone was looking for it.
Silly Billy
07/19/2012 09:30 pm
I now have 1/2 the verified pages I had before in April. Instead, I SHOULD have at least twice as many! This thing is STILL not ready for prime time. By the way, my new graph shows ALL the data points for every day going back in time, which is far different from the 1 day shown here. Cheers!
Jonny Ross
07/21/2012 04:02 pm
Thanks so much for making me aware, its a good feature!
Elwyn
09/06/2012 09:10 am
I have implemented this successfully on my blogs but not seeing any graph or pages under the Author Stats