The way Gearbox has been talking it definitely sounds like the Wii U will be the version to get. That said this quotes worries me a bit from an article at IGN talking about its new rendering engine that will be the next generation in graphics technology.

"He also specifies that Aliens: Colonial Marines will make use of the deferred rendering engine on PS3, 360, and PC. The Wii U version presumably won't use it."

http://games.ign.com/articles/122/1222270p1.html

Worries me slightly as it would match what those two developers said that the Wii U can't match the graphic capabilities of the other systems.