Just playing a guitar isn't hard: you buy a guitar, look at a book to learn a few chords, practice putting your fingers in the right places, and strum away at a song. But playing a guitar professionally is very hard; it takes time and practice and dedication. Likewise, Rock Band is a good time: figure out when to strum, and wail away on some pop tunes with your friends. But Rock Band 3's Pro mode isn't kidding around. It's got a difficulty curve almost as steep as the real thing, and while you still probably won't be able to play stadiums after beating a song on Pro Expert, you'll have a very good idea of what it takes to do so.

We got to play a couple of songs with the Mustang Pro Guitar controller shown off by Harmonix and MadCatz at E3 this week, and it's a beast -- each string of 17 frets on the guitar is an individual button, and there are six strings where the strum bar sits. Harmonix really wanted to make a real guitar as a controller (and it eventually did with the Fender Rock Band 3 Squier), but that "comes with a little bit of baggage of its own" in the form of tuning and calluses. We asked if the developer tried a touch-based system, but reps passed on confirming any prototypes, instead saying that the 102-button setup was the best solution it found.