It was an excellent game for Ludum Dare! I can't believe it turns out the compass was just Safari though. I was expecting it to be a bit more. :P
I agree that the bosses were great. I especially liked Safari - if I were you, I would have spent 72 hours just to get those arctangents right. :) However, I do think that Chrome was too similar to Opera (which is why I didn't give 5). I understand that you only had 72 hours, though.
As for the graphics, they were very MS Paint-ish. My only complaint about them is that the brick wall didn't look MS Paint-ish at all. By the way, did you really draw the pictures in MS Paint and import them into Flash? (I'm guessing you didn't or you wouldn't have HD graphics - MS Paint draws BMPs.)
Overall, it was a great game with great bosses. I hope to see more jam entries from you. :)