It was a little surprising that the Packers released LB Robert Thomas. On last season's team, only LB Nick Barnett showed more speed than Thomas, and Thomas seemed like a good candidate for weak side linebacker. But the Packers have a lot of candidates competing to start alongside LB A.J. Hawk and Barnett (LB Abdul Hodge is a tentative front runner) so it doesn't hurt at all to release Thomas. At the bottom of the article, it mentions that the Packers saved salary cap room when they traded WR Javon Walker too. The Packers are padding their NFL lead for the most unused salary cap room.
The Packers also signed a few more undrafted free agents. None of them really fills a need and all appear to be signed to add depth during minicamps and training camps. Sometimes these guys stick with the team, such as LB Roy Manning did last season, but they are all longshots.