Rock Band may face an uphill battle against reigning iPhone music game champ Tap Tap Revenge, but the Bluetooth-based full band multiplayer and Facebook-enhanced online, as well as the name, provide some advantages.
Rock Band "ships" with 20 tracks, with more available in the in-app store. If, you know, $10 isn't enough. And when downloadable tracks are involved, when is it?
Rock Band ($9.99)