If the next Mario game rules and it would cut some costs, then I could care less about DVD or Blu-Ray playback. I don't even watching Blu-Ray movies, and I have like 4 DVD players in my house.
If I would consider buying a Wii U, I would want:
1. A Steam/Xbox Live like experience for free, and an amazingly loaded and featured App Store like Apple's (yes I said it)
2. Great games.
3. Price tag lower than $400, which includes at least 3 controllers in the price.
4. HD option for Wii games (if you used the Dolphin emulator and enable AA, it actually looks decent, though not the level of Xbox 360)
5. Good graphics (I'm not looking for over-the-top no jagged edges FPS on a 97" screen, but at least at the PS3 level).