Thanks a lot guys!
@britzl - Hmm, I never even thought about making the bullets not wrap. Do they wrap in the original? I did make the bullets last a very long time, so maybe that's the issue. Your ammo/energy regenerates slowly over time, and you get a shot's worth back when a bullet hits something. I was trying to encourage accurate shooting and penalize random blasting away, but maybe it's just not fun. I'll fiddle with it.
@Tomires - Thanks! It's a very simple camera shake, I just offset the camera randomly within a radius every frame, and linearly reduce that radius to zero.
@loren.hopkins - Thanks! They are just painted in photoshop.
@sergey.lerg - Also thanks! Do you mean the "asteroids" are too small, or are you just talking about their appearance? I'm not sure about their design yet. I was thinking of using a shader to make them look like jelly blobs, but more traditional polygonal rocks would be simpler . . . I'm not sure about the collision area, wouldn't it be weird if things passed right through your ship? I actually made the ship longer on purpose because I like how you can turn sideways to slip through small spaces (or fail to do so).
I updated the build late last night with some new button graphics. No more dumb white boxes! I still need to remove the "quit" button in the main menu, it doesn't make any sense in a web game does it . . .