The enhanced Bluetooth provides the ability to have:
- Audio Streaming from the phone to the car via Bluetooth
- two phones can be connected to the car at the same time
- voice control (see note below)
- Office functionality
- Armrest snapin preparation for a phone / device. You can buy the additional snap for your device to allow you to use the car ariel. Based on what I have read the snap in charges the device at a faster rate then the standard USB.
The enhanced Bluetooth was removed by bmw from the pro nav pack when they upgraded the pro nav system this was in the second half of 2012 I believe.
If you don't buy the enhanced Bluetooth but have the new pro nav you can code the car to enable all the features of the enhanced bluetooth apart from the snap in feature. This is due to the car having the hardware to support the enhanced Bluetooth but bmw not enabling it.
If all you want is to USB connect a device to the pro nav without a snap in then there is no real need to get the enhanced Bluetooth.
I'm not clear about the album artwork as this seems different from device to device and lots of people seem to be using a memory stick for music.
I personally went for the enhanced Bluetooth as want the snap in.
Others have also commented that they have voice control without the enhanced Bluetooth.