audio aux input
 

Is this just the audio cable? Aux Audio Input

Can I get that at my local radio shack or something? How's been your experience with doing mp3s through a smartphone (HTC Incredible incoming)... any technical issues?

You can use any 3.5mm to 3.5mm cable. There is nothing special with the BMW one.
You can find it at Radio Shack or any computer store.

I haven't tried a phone yet (using iPhone Y-Cable) but I used my iPod a while ago and the quality was fine as far as I remember.

I have a Driod Eris, similar to the Incredible you are expecting and no problems here. I use a standard cable. I just set my media volume to about 3/4 or 4/5 so the music doesn't distort but it sounds great! And yes just a regular cable from radio shack should do.
I have tried getting just a regular USB cable and plugging it in to the USB port and setting my device to disk mode hoping it would show up on the iDrive but it didn't work, it would be nice to be able to control the music on the screen...

after a few mins of surfing it seems
that part number is sold as a 'kit' that
must be installed and programmed at the stealer.

thanks for the info, so I won't be able to get a song list on the idrive at all? Everything is controlled through the phone, which must have its display on the entire time?

I guess it sounds like it's as if I were using a headset for the phone... the headset being the car speakers...

I have the BMW kit and absolutely love it. Of course the dealer is a rip off but the convenience of leaving my ipod in the arm rest and never seeing it to control music etc is great. Seriously thinking about getting DICE for my M now.

Nope no song list to the iDrive, I didn't really fiddle too much with it but I dont think there is a way around that. And with the phone I just select a song I want to listen to and lock the screen and it continues to play. And from the lock screen there is quick music controls. It's not as bad as it seems