Just found this post on the BMWM5.com board. I guess someone(FlyM5) was able to hook up an available voice recognition module into his M5 with NAV. Only works with 01/00 E39's or newer. Sounds like an interesting upgrade. ANybody up for it? I'll check Pacific BMW and see how much the parts are.
regards arnold
ps. scroll thru the posts..it would be interesting if it works with the audio controls too.