I'm not super excited. I might not even buy any launch games, besides the pack-in Nintendoland. That said, here are some reasons I decided to preorder.
1) Even though I still have a perfectly working Sony CRT, I'm never going to game on it again. That TV has been relegated to the guests' room. It's the biggest reason I skipped the Wii, and I now welcome Nintendo to HD gaming, wholeheartedly.
2) There are announced games that I am already looking forward to, so it's more than just blind expectations of good games being made for the system.
3) Since I already decided I want the system, despite not being too interested in the launch games, I also don't want to have to deal with another Wii scenario, e.g., having to line-up overnight for a Wii even a year after launch. I did this for a young family member who wanted one.
For me, I foresee the Wii U being an exclusives machine. I don't see myself buying any multiplatform games for it, especially once PS4/720 rolls out.
I'm totally buying most of my multiplats on Wii U and I'll give you two reasons why.
1) I can lie down on my bed and play games straight off the controller
2) no split screen multiplayer