Wow.
Just read this post by Mullenweg on the Gravatar blog. I had no idea this was in the pipes, but man, am I glad!
BTW, all the premium Gravatar features are now free, and it’s being merged with WordPress.com’s avatar service. So be on the lookout for many more commenter icons on the way!
It’s funny… all it takes is a little thing like this to brighten my whole day. 
This is very good news. It never seemed to work for me.
It worked! Now I am as happy as you!
Hooray!