This TV ad does; it features people playing the Squier, Mustang and keyboard with cymbals on the drum kit and multiple microphones (all pro band). There are quotes from reviews praising the pro modes and the little voice-over at the end mentions them: "Rock Band 3, now with keyboards, real instrument game modes and support for over 2000 songs."
I posted a poll shortly after lauch asking whether people had seen that ad; most respondents hadn't and the largest group who had saw it non-primetime on a cable network.