X360 for me, but these are issues on all consoles, probably:
1.) The menus/interface is SO much less intuitive than RB2 (can't sort songs by DLC vs RB1, RB2, RB3, etc... wtf?)
2.) In the non-gameplay screens (ie. when not actually playing a song), why am I listening to musak? GIMME TUNES! You have a huge songlist, use it!
3.) Between songs/animations the load screen is an abrupt and PAINFUL stark WHITE. On a 60" LCD in a dark room, the 5 of us playing were all complaining about that. Seriously, my wife was getting a headache.
4.) Auto-calibration is fantastic! But you should mention in the calibration start screen that you need full, fresh batteries in your controller for it to be effective. A set of half-power AA's wasn't getting any reading, and had us dying after 20 minutes of video-cal on auto. Again, 60" tv, dark room. OUCH!!!
The whole game feels less polished than RB2 when it first came out. Your animations (particularly the singer) aren't as song-appropriate. My wife's singer looks like a spaz as often as not mid-song... My drummer is worse.
The whole Challenge/Goal-oriented progression is a valid approach, I suppose, but it lacks the sense of adventure/ worldwide growth of RB2.
There are some serious issues with the singer activating Overdrive. Serious.
And the lack of local PVP? Come on, guys... The game supports 2 guitars and up to 3 singers as a default. And in RB2 you could local Drum Duel. Did the design team just forget what makes this game so cool? It's a party game, probably the best one ever made. I get that you wanted to teach Little Jimmy how to play a real guitar, but the backbone of this franchise is the plastic-instrument wannabe crowd. We LIKE goofing off in our living rooms drummer vs drummer, singer vs singer, dare I say keyboard vs keyboard?