It is kind of unusual that there are still a lot of unsigned point guards in the NBA right now. Steve Blake, Mario Chalmers, Norris Cole, Bryce Cotton, Jordan Farmar, Kirk Hinrich, Ty Lawson, Andre Miller, Xavier Munford, and Phil Pressey round out most of the bigger names available. Among that group, the two former Miami Heat are on top of the list. While the teams are signing big men left and right, these guys are certainly still serviceable and can still contribute to any team that would sign them.
Probably because the evolving paradigm today is for big men to shoot and make plays. We ain't gonna see another Stockton-Malone duo sometime in the future because the borderline between player roles within the court are becoming more and more blurred.