Addendum to my previous post:

I also want to point out that Rock Band gets this -- but Guitar Hero does not. RB makes it super easy to use all of your downloaded content ("stuff") with RB2. It also works with pretty much any instrument controller. GH doesn't work with RB controllers -- on purpose -- and the GH: Aerosmith expansion didn't work with any GH3 downloadable content. Also, RB2 very cleverly made it easy to re-create your RB1 characters, although if they'd really been on top of it they would have included character import from RB1. Guitar Hero 4: World Tour wants very hard to win on features alone, and I will admit it's a compelling list of features. But... I already have the RB1 instruments, and the RB1 songs, and a bunch of songs I bought. I don't think the slidey touchpad frets are going to be enough to justify having to buy all new stuff. Did I mention I also hate to move?