This seems like a pretty nice port of bubble bobble. :) A bit of an odd thing to do though..?
Bubble bobble was ported to most 16 bit formats, so it's easy to emulate the original.. You can emulate the entire BB series of arcade machines using MAME..
"Bubble Memories" is the official arcade remake, and is like this with knobs on really - if people's macs are fast enough, hunt that down too.
Ok arcade emulation isn't exactly 100% legal, but neither is ripping off some other companies' game. Especially when the series still gets new games occasionally ("bubble bobble old and new" on the GBA being the latest game I know of).
Keep up the good work though, but I wish it wouldn't distract the devs from original games too, which I feel could be incredible, as they obviously have a lot of talent, which is sparse in the mac shareware games scene.
It's like a really good band which only does covers. Frustrating. :D