The new dock connector doesn't support analogue audio out anymore, it's purely digital.
I'm fairly certain that the AMI uses this analogue signal for audio, meaning you won't get any sound with the new devices. Whilst the adapter would allow you to physically connect them to the AMI cable, without the audio out you're not going to get any sound.
Not getting into a debate about phones, let's not go there
As for USB, I used to use SD cards before I had AMI but the problem was you just end up browsing the folder structure on the card so can only search your music one way. With the iPod connection you can browse by artist, album, genre and so on which makes life so much easier.
Ok, been doing some more reading.
It appears that the adapter does support analogue audio out. It incorporates a DAC to do this and this is possibly one reason why it's not cheap.
The "iPod out" which Apple mentions isn't supported doesn't refer to this, but rather a protocol which allows a dock or accessory to receive track names and information so it can display what's playing. My bad on this one - I presumed iPod out referred to the audio itself.
So we now have another question - does the AMI rely on this "iPod out" protocol to display track information or not?
We really need someone to try an iPhone 5 or new iPod Touch with the AMI to see what happens. I don't know if I'm prepared to take the risk or not just yet :/
Nope....
Apple didn't send out my converter with my iPhone 5 order.
Spoke to them and they are sending one out when a new batch comes in free of charge. Will let you know but I expect it will be a couple of days. I asked if it would work with the Audi AMI system and she didn't know. Nice confidence boost there!