It's ok. Great concept, though reminds me of Cool-Natio without music (as he made something sorta similar), but the mechanics, graphics, and actual game part aren't great. I'm assuming this was a 'demo' version in the sense that it will be greatly improved, but assuming it is, it will be sweet.
Blaxxberry
I don't know about down for holding a color, maybe space. The gameplay is interesting though, and I'd definitely recommend expanding on it. The animation is also nice and simple. For more levels, I'd recommend more colored things to interact with, more colors per level, and colors which move around.
johnfn
Coolio. Fair suggestions, I'll get on it!