They're claiming that Rock Band 3 will feature a keytar. A keytar? Come on that's lame.
Ars are all speculating that a new "Pro" mode will be included "that will require proper technique, and may lead to actual skills on guitar and bass". Yup - 'cos pressing coloured buttons is exactly the same as playing a real instrument.
Of course, this is all unconfirmed (though Ars are a trusted source). Hopefully our light-up keyboard will still make an appearance at E3.