I don't particulary trust iPod adapters in cars because Apple could simply change the dock connector specifications etc such that an older model BMW iPod interface no longer works with newer iPhones/iPods. This has been true as recently as the iPhone 3G compared to the original iPhone on older iPod adapters in other cars. The aux in port would be enough for most people. I can't talk on how user friendly the GUI on the iDrive is when controlling an iPod but in my experience with other manufacturers' systems, it is far harder and clunkier to use than on the iPod directly. The only thing that is definitely better with a USB/iPod adapter vs Aux in is the ability to change tracks up and down using the steering wheel controls.

Bluetooth, however, is something I would never buy a car without again. In fact, for myself looking at second hand cars, I'm not even looking at cars without it (well, no cars without the Media Package that they did here with Sat Nav, Bluetooth etc - same as the Technology Package in the US.

I'd also go for heated seats. Again it's something I will want in any car of mine from now on - the option of staying warm without having to have the engine on is worth it in my opinion. Also, X5s that don't have front seat heating have two buttons blanked out which think makes the car look a bit 'cheap' but maybe it's just me that spots things like that in cars a mile off.

I don't see the point in the smartphone integration and besides which, I think you have to buy an additional cradle at $100+ or something per phone model you want to use with it. If it let me use the TomTom app from my iPhone on the big iDrive screen or something then I'd go for it in a flash but otherwise, I don't see the benefit.