Luigi's Mansion 2 was the single game that made me the most excited, with a close follow-up by Paper Mario 3D (even though I 100% knew that one was coming).
They're doing a SSB game for the Wii U, and a SSB game for the 3DS. Apparently, there's supposed to be some sort of connectivity between the two, but it's not as if we'll get to know anything until we find out more about the Wii U itelf.