I like this idea.
It might even be easier to implement than hand gestures, especially if, during installation, we could run through and speak a whole range of commands and have them recorded and saved somewhere so that recognition would be easy after that. Perhaps this could also be used to implement passwords for different users.
The Archers - give it a rest already!
i7 Quad core 2.66 15GB ram, Windows-7 64-bit, Nuendo-7.1 64-bit, Wavelab-6, 2x MR816CSX, RME FireFace UFX, SmartAV Tango, MOTU Express 128, UAD-2 Quad, Lexicon PCM-91, Lexicon MPX-550, TC-Fireworx, Halion-5 (never used), Halion Sonic (rarely used), Kontakt-5 (used all the time), Roland V-Drums TD-20X
Cubase iC Pro for iPhone and Android (killed by its parents at birth)
Omnisphere, Trillian + loads of real instruments.