Call me daft, but I'm fully expecting Smash Bros. 4/Smash Bros. 3DS to at least get a confirmation. At the rate Nintendo has been milking out some of their Money-printing franchises(SMG2 comes to mind), and the recent explosion of Fightan Gaems as of 2009, another Smash Bros. vehicle only seems like the logical next step.
Also, SSBB was released 3 years ago, which is like, 1 year longer than the gap between SSB and SSBM, so yeah.
Besides that, I also somewhat expect Nintendo to announce an HD console. Since the 3DS is going to be as powerful as a gamecube, it would be a bit odd for their handheld system to be about as powerful as it's home counterpart as well. Also, it would print money.