It's really only the new Mercedes' and Lexus' (Lexi?) that are starting to have that. Aftermarket stereos have had the functionality for YEARS, but factory systems are always nearly a decade behind (I remember how maybe a year or two back many manufacturers were making a big deal out of their cars' stereos being able to play these crazy things called MP3's... Whilst aftermarket, even dirt cheap aftermarket, stereos were doing that since the late 90's...
Yeah, I actually had one of the first aftermarket stereos that had mp3 capabilities, but that was two cars ago for me. Is it really that hard to put a USB port in the dash and be done with it?