Visit the Papa Cass weblog at http://papacass.blogspot.com/The NBA's free agency period is less than a week old, and already we can see the Cavaliers' Central Division is going to look quite different when the season starts.The two biggest free agent moves of the offseason so far have occurred in the Central. Late last week, the Pacers' Peja Stojakovic announced his intentions to bolt Indiana for the Hornets.But the real bombshell hit yesterday, when a disappointed Ben Wallace announced he intends to leave the Pistons to sign with the Bulls.Reportedly, Wallace is upset with the Pistons' offer to him, and felt the two sides weren't going to bridge the gap anytime soon.Two years ago, the Pacers and Pistons were the Eastern Conference's biggest rivalry. They were unquestioned as the top two teams in the Central.Now, depending on what type of offseasons the Cavaliers and Bucks have, Indiana and Detroit might be the bottom two teams in the Central once training camp starts.(I should note that being the bottom teams in the Central is still pretty good, considering all five division teams made the playoffs this year.)The really surprising thing is the Bulls could trump the whole division.Adding Wallace and first-round pick Tyrus Thomas to the mix gives the Bulls a deep, strong, athletic frontcourt to go with a very good point guard in Kirk Hinrich and very solid role players in Ben Gordon, Luol Deng, Chris Duhon and Andres Nocioni.If GM John Paxson hasn't succeeded in finding an heir apparent for Michael Jordan's Chicago legacy, he has certainly succeeded in building a deep, talented roster that should look very familiar in structure if you are a Pistons fan.The only downside to Wallace is his advancing age. He's 32, and his athleticism will begin to wane on the Bulls' watch. But for at least the next couple of years, the Bulls now have an unparalleled defensive presence in the frontcourt.It's not too much of a stretch to say the Bulls are going to be playing deep into May next spring, and might even broach June.Don't count out the Pistons and Pacers just yet. They have among the most resourceful front offices in the league. You can bet Pistons GM Joe Dumars is plotting his next move already. But the playing field has been dramatically leveled among the Central's five teams in the past week. Suddenly, it's Paxson, not Dumars, who looks like the alpha dog among division GMs.