From the Press Release:
"Forwards Angelo Esposito, Riley Holzapfel, Rylan Kaip, Andrew Kozek, Jordan LaVallee, Brett Sterling and Anthony Stewart, along with defenseman Chad Denny and goaltender Peter Mannino will report to Chicago. Forward Kevin Doell, who is under contract with the Wolves, has been released from Atlanta’s training camp."
The biggest surprise to me from that list is Jordan LaVallee. He spent some time with the Thrashers last year and played alright. It's really just a symptom of having so many players in camp. If you look at the guys who are fighting for the last spots, there are several solid hockey players who will not be playing in Atlanta at the beginning of the season.
On the plus side, Paul Postma and Arturs Kulda are both still on the roster, so Atlanta-based fans will likely be able to check them out during the preseason games on Monday and Wednesday.