Very Dan Paladin, quite simplistic but still a nice overall game. Upgrades, I do like the idea of getting a new upgrade each level, but why? I mean maybe the boss dies and behind it you see a turbo booster or gun, and then it makes more sence ...
I like the animating and all that but the bosses and levels are kinda repetitive. Although I love the good luck guys, and the bridge. Now I think you need more of that, and keep up the animating and it will be a really nice interactive thing. The bosses are quite dull, I mean the bird has 3 different attacks and takes ages to die. But they're all pleasant to look at. It also takes a while to get the timing - which isn't that badder thing really. Maybe lack of sound makes it dull, I dunno.
It is shaping up nicely so keep it up =]