Official roster now completely set
From Blackhawks.com:
The Chicago Blackhawks have assigned defensemen Cam Barker and Aaron Johnson and goaltender Antti Niemi to the American Hockey League’s Rockford IceHogs. In addition, the Blackhawks have released center Kevyn Adams and center Joakim Lindstrom has been claimed on waivers by the Anaheim Ducks.
I've gotta say that I am pretty surprised to see Cam Barker sent down and not making the roster out of training camp, but apparently he just didn't prove enough to the coaching staff to stick around for now. Also, Niemi may have been sent down but that is likely only temporary, until the Hawks finish that deal for Khabibulin. Kevyn Adams? Good riddance, I won't miss his play too much. And Lindstrom wasn't likely to stick around anyways.
So this is what your official 23 man roster for the Hawks will be looking like for the start of the season: