[jmilton]

Crashing into one of the big hot air balloons is not nearly as satisfying as it should be :)

Just an aesthetic note, but the yellow smoke trail is a bit unappealing. A red color might show up better against the background, and the color does add a hint more excitement.

Or perhaps some simple customization where you choose your smoke color at the start (also functioning as the start button).

Other than that... very fun. Definitely could get popular on facebook with challenges and best scores/times for each level and overall, or just as a fun way to pass time.

[jmilton]

and maybe I didn't get far enough, but this type of game definitely needs moving rings. Adds tons of extra challenge and excitement (and if you have some smooth rotation effect for the rings as they move it would look pretty cool too).