Nintendo showed a brief montage of already-announced third party titles that will coming to the Wii U at or around launch. Many of the games shown were announced for Wii U at E3 last year, including Darksiders 2 and Aliens: Colonial Marines, but there was one notable exception.
Mass Effect 3 will be coming to the Wii U.
At the time, Nintendo didn't discuss how the Wii U version of the game would distinguish itself from the PS3, Xbox 360 or PC, which have been out for months now, but I'm guessing if you look at the demonstration of what Rocksteady is doing for Batman: Arkham City - Armored Edition, you'll have a good idea of what to expect.
Aside from Mass Effect 3, here's the full list of all the games shown during that initial third-party Wii U montage:
- Darksiders II
- Tank Tank Tank (Namco)
- Tekken Tag Tournament 2
- Trine 2
- Ninja Gaiden 3: Razor's Edge
- Aliens Colonial Marines
Later on in the show, Ubisoft also showed a few multi-platform titles, including Assassin's Creed III and Avengers: Battle for Earth.
It doesn't have everything, but the Wii U looks like it'll have at least a few multi-platform games on the way.