It looks like the natural evolution of music rhythm game peripherals will finally include a keyboard. A screengrab taken by Kotaku during a demo of Rock Band: Green Day shows a teaser image for Rock Band 3. Of note are the different musical instruments included in 5 different icons.
Guitar, drums, bass, and microphones were always bundled with the software, but the fifth icon is definitely showing a keyboard. Likely using a MIDI keyboard, fans will be able to play along with the game’s set list, presumably as long as the song of choice features a keyboard.
On a side note, I can play a mean “It’s A Small World” on a regular keyboard. Be prepared Rock Band universe.
