Decent
Hm, it was good enough to kill a few minutes, but it get's boring after a while. Sure it's fun, but what is there to keep me playing it? Usually games like this have a storyline or plot. All I saw is controls. And the clor scheme is just too... Well, monochromatic.
I'd give this a 4/10, but I have to admit that the concept of it is pretty decent, so I'll score you a 6/10 for trying. And I guess you had fun making it as well. Keep it up, and you'll eventually improve. Maybe in a few months time, I'll be seeing full-on frontpage games from you, so don't give up on it so soon!