I had some time to stop by Nintendo's booth during E3 yesterday and get up to the Wii U special area of awesome hands-on fun times. Battle Mii was the first game I tried out and my first reaction to the Wii U controller was that the gyroscopic controls are deadly accurate. So much more impressive than the 3DS gyro-controls, in fact.
In Battle Mii, I was playing on the Wii U controller as a Mii piloting a miniature version of Samus Aran's spaceship. Moving the ship around requires both analog sticks, camera controls are associated to how you move the Wii U around in your hands and shooting is on the right trigger.
The overall goal saw me having to shoot at two other characters running around as Samus on the TV (via Wiimotes) in front of me. The basic feel of the match reminded me a lot of Star Fox as everyone was gunning for each other. It did feel incredibly unbalanced though as I had the better advantage staying in the air while the others were running around on the ground.
As for the Wii U controller, I was honestly surprised at how comfortable it feels to hold. I thought I was going to hate it, but it felt fine. Now I just want to see some solid core games to get a better judge of the thing.