Cocos 2d

I'm making a fairly basic game for the iphone in all 2D. It will be a rhythm game. Any opinions on Cocos 2D? Is it fairly fast and have a good community backing it? I was thinking of going the OpenGL route, but it may not be necessary. And I wouldn't want to over complicate things for my first iphone project.

[Edited by - Arbel on June 26, 2010 9:30:35 AM]