We're at The Contemporary right now. In fact, I'm typing on one of the computers that they have in each room.
We just got here today, and the only Christmas-y thing I noticed was a tree out front. There may be more, but if so, it didn't really stand out. I'm fine with that, because I really didn't come down here for a "holiday-themed" trip, but it might bother others.
Otherwise, the only construction I noticed were the cranes outside, which don't impair the view, and the lobby on the first floor. Although, if I hadn't known that there was construction going on, I wouldn't have realized it. I would have just thought it was a small lobby.
Overall, it's great. Really convenient and rooms are spacious and look great. Not a lot of atmosphere though. It just seems like a "W" hotel plunked down at DisneyWorld with a Monorail running through it.