I just feel that, on a whole, Rockband is more fun and this is for a few reasons. On GH, all the songs, obviously, revolve around the guitar, with crazy solos and chords. In RB, you get a mix of very different songs that top priority isn't always the guitar. This leads to a larger reach for the music. Sure, you get some crazy songs in GH but it just feels that RB covers more.
As for Flyleaf, I didn't read all of what was said but my friend said that Flyleaf is going to be at the fair, which is pretty cool. ^^