The former owners of Harmonix, Viacom, have decided to sue the Rock Band and Dance Central developer for the royal sum of $131 million according to the Hollywood Reporter. According to Viacom they paid to much for the company in bonuses back in 2006 when they took over the company, and now they want most of that money back. In essence they are saying "we may a bad business decision, we take it back!".
The business dealings between Harmonix and Viacom have been infected for quite some time, and Harmonix claim Viacom owes them $13 million for unfair business dealings. It remains to be seen how the thing plays out in the courts, but its fair to say that lawyers are going to be the only real winners in this whole mess.