Here's my Wii U prediction for E3.
-New Super Mario Bros Mii is a real game now with HD visuals
-Pikmin 3 is finally shown
-Sequel to Donkey Kong Country Returns
-New Wii Sports game for the Wii U
-New Wii Fit for the Wii U as well
-A racing game from Monster, either a new game or a revival of an old Nintendo racing series.
-A new Wario Ware game taking full advantage of all the tablets features
-Monolith Softs Wii U title will be reveal(this is quite likely since they've already confirmed they're working on a Wii U game.
http://andriasang.com/comwku/monolith_wiiu/)
-New game from Good Feel will also be shown
-Small CG trailer for next Smash Bros will be shown to give people an idea what the Wii U might look like but no gameplay since I doubt they'll have much done by E3 if Sakurai just finished Kid Icarus now.
For third parties it's not worth predicting anything specific since we know it's going to be port city. Basically any upcoming multiplatform game will get a Wii U port and that's about all I expect from them. Except for a few niche Japanese games that usually become exclusive to Nintendo platforms for a while.