The graphics actually look pretty cool right now. Even with the currently-simple mechanics, the smooth animation and physics are somewhat mesmerizing.

I'm getting a "Space War" vibe from this game. Not that this game is like "Space War," but it almost has that feel of the classic vector-graphic games like Space War, Asteroids, Star Castle, and so forth.

Are you planning a "single-player" option? You may have mentioned it in a previous blog post, but if so, I don't recall off-hand. I can see the current mechanic being used in a single-player "alien invasion" type of game, where you must shoot invading space battleships, missiles, and so forth. It may not be what you had in mind, but it probably wouldn't be that hard (comparitively) to implement.

I noticed that it appears the player can shoot an unlimited amount of bullets! That's pretty cool; I can see myself "raining hell" on an opponent!

Also, it appears that the celestial bodies all exert the same amount of gravitational pull. If so, I'm not sure that's a bad thing. It might be a good thing, player-wise, depending on where you take the gameplay.

Anyhow, the basic mechanics so far look pretty promising! Looking forward to the next updates!