SPQR - you will need a BMW cable. The centre console has 1 AUX and 1 USB port. Data is transfered to iDrive via the USB port and is also an iPod Charger.
The AUX Cable channels the audio. THe rest is via the wheel.
Check out the iDrive information on this CNET CarTech video:
http://cnettv.cnet.com/
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