We've reached out to Activision for some kind of comment or confirmation; however, until then, speculation seems to be the name of the game. G4 is guessing keyboard, which is all well and good. And who knows, it may well be a keyboard. We're not oracles here. But as long as we're just guessing, why not guess a little bigger, y'know? That's why we're happy to announce Joystiq's official guess for the rumored new Guitar Hero World Tour peripherpal: keytar.