For those of you too lazy to click on the link I've cut and paste his comments below (ltc is the user):
"FWIW, PAG took a different approach to iPod integration compared to others(VAG, BMW, et al). PAG decided to place the iPod adapter directly onto the MOST ring as a discrete device/address/node.......everyone else decided to attach the iPod directly to the headunit. PAG's took a bit longer to integrate/validate with both MOST infotainment platforms (955 vs 9x7).
There will likely be a S/W update to the PCM to add the iPod HMI...the H/W install is fairly straightforward.
(I designed both and sort of prefer the MOST implementation for various reasons)."
"The 'docking' connector on an iPod has many pins/features (revealed by Apple once you sign agreements, agree to licensing fees, royalties on each unit shipped....not a small % BTW); one is a UART connection.
The UART handles command/control/status, so you can pass list information, etc from the iPod, over MOST (22Mb/s is PLENTY for this ) and to the headunit for display via the HMI....all a function on how the PCM's HMI is ultimately configured/designed (how often to pull data over the UART, how much, how fast the iPod can download the info, how much time a human is willing to wait for updates...people typically have 3-4 seconds of 'patience' before they think something is wrong....re: the elevator button experiment in human factors design)
PAG made a decision a while back to 'decouple' the introduction of infotainment devices from new car releases; previously, they would release everything at the same time (e.g. Cayenne with MOST with Centerpoint surround processing).
The only decision left at PAG is when to release the iPod integration as an AfterSales item and on which vehicles first (9x7 or 955). It has been 'shown' on a 997TT to date.....oh yeah, and exactly how much to charge (marketing ALWAYS has the final say on everything at PAG)
It's coming, those who want it will just have to be a bit more patient."