Update: MTV has responded to our inquiry over the keyboard icon, stating that at this time it doesn't "have anything to announce", but instead we should "stay tuned for news about Rock Band 3 at E3". Awesome. Keyboards. FTW. Probably.
Original: Harmonix has released a demo over on XBL for Green Day: Rock Band on Xbox Live. Good news, that.
On top of that though, at the end of the demo is a tease for Rock Band 3 - which just so happens to show a keyboard icon.
Included with the keyboard icon, is one showing three mics - which suggests three-part harmonies won't stop with The Beatles: Rock Band.
Keyboards for music games have been wanted by some for quite a while, but considering there's 10 scales on an actual piano, we're wondering how Harmonix plans on making this work.
We'll send a mail.
Check the picture of the icons out for yourself over on Kotaku.
Green Day: Rock Band hits the US on June 8 and the UK on June 11.