Rock Band 4 (PS4/XBO) Coming Out This Year. Supports Old Instruments and 2168 Songs!(Update) Added a Q&A portion from the team.

[Darwinianevolution]

Why isn't it coming to the WiiU? If all of the devices are compatible with the Wii, there's no reason to... Oh, right, EA is the owner and distributor of the game. They wouldn't support the U even when it's so obvious.