Rock Band has been ported to the iP's. I was pretty excited when I found out about this thing, and downloaded it as quickly as I could. This is my review.
Graphics: 4/5 Looks really good at the menus and everything. In-game, there is simply a loop at the top of the song being played, but it's not accurate.
Sound: 4/5 A pretty good soundtrack, although there are some songs that are so overplayed I'd rather die than play them. Cool thing is, you can purchase 2-song packs for $1 each.
Control: 2.5/5 The game is not a joy to play for the most part. If your timing is perfect, it seems you will STILL miss notes, and quite often when you hit two notes at once, they won't hit at the same time, even if you tap at the same time.
Fun: 3/5 Rock Band for the iPhone/iPod could be a good game, but the control ruins it. You'll find yourself missing notes when it's not your fault, and it is just very frustrating. Also, to go from medium to hard (there is no expert) is a huge step. Just saying.