scenic locations in tokyo during winter?

In my opinion Autumn is the most scenic with all the fall colors in the trees and plants, but my trip this year is the week after christmas.

I was wondering what areas are good for sightseeing during winter? Will the park trees all be bare?

Parks and gardens in Tokyo are somewhat bare after mid December, but they can still be nice. Apart from the parks' appearance, Tokyo is the pretty much the same year around.

Skiing is an option during winter:
http://www.japan-guide.com/e/e2262.html

And winter is also the best season for hot springs:
http://www.japan-guide.com/e/e2292.html