According to a source over at Develop, Nintendo seems to be working on a way to support two of their tablet controllers for the Wii U. Specs like RAM amount and CPU speed also seem to not be final yet.

When the new console and controller were unveiled at the last E3, only one tablet could be used per console, with other players using wiimotes. The use of more than two tablets in use at the same time is not being considered, however.

“Nintendo now know they absolutely need to support two tablets,” the source added. “At E3 they didn't commit to this, but they know how important it is to make it technically feasible to support two screens. Even if that affects framerate, as a developer and player, I don’t care. It needs to work. Developers will design appropriate games for this. If you’re building a quiz game you’re not going to give a shit about the framerate.”

I think enabling support for more than one controller is a good thing, I'm all for more gaming options. It could also make for interesting two player gameplay and interactions, if game studios implement it properly. We will probably see the final version at E3 2012.

[Develop]