Hey, you can now add a profile user as a favorite in Google Books :
http://books.google.com/books?uid=132233764003563318
And then, profiles will appear in a colum on the left.

It's pretty cool if you know a guy who reads only good stuff ...

This is an old feature.

http://googlesystem.blogspot.com/2008/02/google-book-search-adds-social-layer.html