i know for a fact it is standard in LS's, not too sure about others, i think i've heard that it's at least available in teh IS, and i'd almost guarantee it's in teh GS430 if not in the 300 as well.
Bluetooth = the sexiest thing in the known universe. Through my in car computer, I have it in my car.. yay.. But I'd love to have a car with it built in