I was surprised (by my mother) with a Wii for Christmas - really more of a "family" present, I think, than something just for me...
Honestly, my impressions of it are the same as they were before I got it (I had played at a friend's house): It is fun, is something different - moving around instead of just sitting and pushing buttons - and it's something we can do together with the kids and others who are over. That being said, though, I wouldn't have bought it for myself, and I don't see myself buying any games other than Wii Sports and Wii Play (part of the Christmas gift) for the Wii, and as such it will have limited appeal - at least to me.
I think it will continue to be fun to do with the kids and guests, but for the most part it won't by my first choice when I want to play a game by myself. In short, it's one of the best toys/party games ever invented, but nothing more. Again, just my opinion.
After playing Uncharted: Drake's Fortune, it's hard to even look at the graphics on the Wii, but you can get past that (at least for a while) because it is fun. Even the great "innovation" - the motion sensing - is really not that great, if I'm being honest. Again, it's a fun differentiator, but it's also inaccurate and twitchy at times - sometimes to the point of being frustrating. Once again, fine for playing with the kids and at parties, but less than I would expect from my next-gen gaming system...
Anyway, I don't mean for this to come across as negative - I'm glad we got ours and we play it almost every day, but I wanted to give my honest opinion of what it is, and what it isn't.