This feeling. I can't tell whether it's relief or apathy. According to a post in Neogaf from Jeremiah Slaczka, creative director and co-founder of 5th Cell, the Wii U most likely will not have a centralised 'achievements' system in place for the console. Nintendo is leaving it to the developers themselves to decide.
"There are no Wii U accomplishments that are system wide," he posted. "They are up to the developers to include or not include."
5th Cell, set to release Scribblenauts Unlimited on the console has "loosely" added 'Global Starite Shards' which Slaczka described as a "giant checklist of global things to spawn and do in the game that aren't area specific".
Now that I think about it -- the feeling is relief. I always sort of enjoyed playing Wii games sans any kind of gamified reward. I think playing a Mario or Zelda game would feel a little bit strange with some sort of achievement blip. Just me I suppose. I felt the same way when Achievements were first introduced with the Xbox 360.