Sure, there is four-device Bluetooth multiplayer, and that's something that Tapulous' game has never had. But other than that, it seems like this is basically EA's cash in on the tapping concept -- the draw of Rock Band has been getting together with your friends and jamming out the hits on those fake instruments, and touching a button-less screen by yourself doesn't have the same effect. Singing is included, but you're still just tapping out notes for that -- it seems like they missed a lot of potential fun there. And even some of the fun things from the console version like the drum fills for overdrive and the character avatars are missing here.
If you don't like the 20 songs included with the game, you can download others at 50 cents (in two-song packs for a buck each), but most people probably shouldn't even bother at that price -- just stick with Tapulous' game unless you really love Rock Band and its aesthetics (even then, I haven't seen my much-beloved Harmonix mentioned anywhere with this port,
Even if you want to try this one, wait for the inevitable price drop -- if the game really lived up to its name as the premiere music experience you'll find on the consoles, it might be worth it, but all indications are, unfortunately, that it doesn't.
Gallery: Rock Band iPhone / iPod Touch