According to a new tweet from Nintendo, they plan to properly reveal three of their biggest first-party Wii U titles in a Nintendo Direct presentation before E3. "We will discuss new Smash Bros., 3D Mario game, Mario Kart and other Wii U titles in our #NintendoDirectNA before the start of E3," reads the missive, which is music to our ears since the console doesn't really have any confirmed system sellers on the horizon as yet (sorry Pikmin 3).
We'll naturally keep you posted with the date, links and on-site embed code for the presentation. There's less than a month to go until E3, so expect firm details soon. Also this.