Funny thing: I liked the old DC controller and the original Xbox controller. As long as you didn't hold them improperly, they were great.
The trick is, you are supposed to actually hold them in your HAND, not your fingers. That prevents finger strain and a lot of the RSI problems people get into with awkward hand positioning. The side of the controller goes into the crease between thumb and forefinger and across your palm, and your thumbs are free to use the buttons while your index and middle finger operate the triggers.
The Xbox controller was the first one I ever had a marathon gaming session with and felt no pain after. Couldn't say that about any of nintendo's controllers, nor the silly Playstation controllers that jab your hand with a too-short flange underneath each side and force you to curl your ring and pinky fingers in to try to hold it up.
It's ergonomics 101.
The other feature I "like" about the WiiU's controller is the theoretical ability to play a game on it while someone else uses the TV. Not enough to buy a WiiU, but I like the concept of the feature. The problem with it is that from what I hear, most companies don't really take advantage of that - they assume you have the TV running the game, and the pad screen available for some other form of readout, and so going to single-screen mode hurts your gameplay options.
I guess that's kind of like with the Wii's controller. There were a few games that used it really well, and a lot of third-party games (looking square at Activision here) where they implemented shitty controls to "show off" the motion-sensing features when there was no good gameplay reason to bother with motion-sensing anything.