Hmmm
I like games like this, because I can do better at these than I can at games like DDR (and while I've never played Guitar Hero, I can see certain similarities).
On a different note, I read through some reviews, including UntrueCastle's, and I agree with basically everything he said. There wasn't that much reaction time, so you could slow down the speed of the arrows, or just make the path they come on longer. And if they covered eachother, you were kind of screwed because it was hard to tell what the covered one was. Problem solved if you have each arrow come down a different path. Also, at a couple parts I thought I was being screwed, and I basically was. On the faster songs, if I missed one note and tried to skip it to get to the next note and catch up, it'd hit me as wrong. Basically, I'm trying to say that if the arrow I hit doesn't match with the one on the line, I shouldn't get punished for it. Also, add a way to give up. At one point I said screw it and wanted to restart, but couldn't and had to wait for the song to finish.
I'd like to say it was good and fun, but I couldn't get myself to play past the fourth song. And I'll admit, it was because I couldn't get past the fourth song. If you CAN get 100% on each of these, that's good because I'd be scared if you, the person who made and knows the game inside and out, couldn't. You have the framework for a really cool game here. Keep going.