It's alright - lots of room for improvement
You've got some good songs on there. American Idiot was very fun to play. The animation was also well done. I like how you made the keytarist respond directly to the player input. However, like many people have already said, you have a lot to work on if you want to make this a truly enjoyable game:
1. Make sure that the timing of the notes is spot on. If you only make one improvement in your next game make sure it's this.
2. You need to make the opening songs easier. I'm pretty good at guitar hero and it took me a couple of failed attempts before finally getting used to the game, so I can imagine that it'd be extremely hard for less experienced players. (And the out of sync notes don't help much either). You should make the notes appear earlier or slow the scrolling down a bit (or maybe try a bit of both).
3. You need to modify the rock meter/penalties to make the game a bit easier. (For the benefit of players:) At the moment the rock meter can be divided into 60 parts. Each time you hit a note the rock meter increases by 1, each missed note decreases it by 2 and each wrong strum reduces the meter by 4!!! If you miss strum ONE note, you get penalised by 6! (4 for the wrong strum and 2 for missing the note) - That's 10% of a full rock meter gone - FOR ONE NOTE. This is far too harsh, especially for beginners. As a suggestion, maybe next time you could divide the rock meter into 120 parts and have correct notes increase the rock meter by 2, with missed notes and bad strums decreasing it by 3. If it's possible, it would also be good if you could make a bad strum overrule a missed note so you don't get a "double penalty" for a bad strum along with a missed note.