So I've had the chance to get through most of the world tour on drums maybe 20 songs or so left to unlock. just some thoughts...
-drums are much harder now for more songs... many songs are arthritis inducing, as opposed to just Run To the Hills in RB1 and I haven't even gotten to the hardest ones.
-no solo mode ala RB1 = fail. Have no idea why they took this out. I play the majority of the time alone on drums and want to know if i'm getting better at songs. I also like to see my list with how many stars I got. They should show both stars and score.
-a lot of the songs you have to play to get to the good songs absolutely suck... ie whacha want... that song is just terrible for RB.
-don't get the RB 2 wireless drums yet. They have all sorts of issues with hits transferring across the pads.
-calibration is better than RB1, but still broken. I had to do a lot of tweaking to get the right settings at least on my parents rear projection TV. They should have left presets in at least for guidelines
-still some bugs, hopefully they will be ironed out with a patch
-20 free DLC songs not available yet unfortunately, I presume they will come out around the time GH:WT comes out so they have a hand to play against them.
overall the game is more like RB 1.5. But it's still RB and worth every penny

8.5/10 IMO