A source at Ars Technica has started the as-yet unconfirmed rumor that the new Rock Band 3 instrument is not a piano-type attachment, but rather a keytar. If you are not familiar with a keytar, it’s pretty much what it sounds: a keyboard with a strap, held like a guitar. The attachment will most likely be made by third party hardware creator Mad Catz, who will be creating the other instruments and bundles for the game to allow Harmonix to focus on software only.
The same source has also announced that there will be a new “pro” mode in the new iteration, focusing on proper technique for each instrument. The idea is that the mode will lead to “actual skills on guitars and bass”, although how this will translate with the game’s button controls is unknown. As yet both features have not been confirmed by MTV or Harmonix.