It appears that there are two options for the '11 Coupe, codes UAV and U2T.
The Base model gets code U2T: Audio system, AM/FM stereo with single-slot CD player and MP3 playback with Radio Data System (RDS) and Bose premium 8-speaker system.
The Performance Collection has an option to select code UAV (standard on Premium and V Coupes): Audio system with navigation, AM/FM stereo with CD/DVD player, MP3 playback, Bose 5.1 Cabin Surround Sound 10-speaker system and HDD-based navigation with XM NavTraffic/Real Time Weather, 8" pop-up screen, Radio Data System (RDS), 40GB Hard Drive Device (HDD), USB with audio connectivity with steering wheel controls. The conflict witht he RPO codes is that the sales brocure indicates the Performance Collection has the 40G hard drive and USB Connectivity (without nav).
My '11 Coupe has Nav and both the 3.5mm and USB in the console.
On prior sedans, you used to be able to get the 40G hard drive without navigation and that had both the USB and 3.5mm jacks (Code U2S). This option now appears to be gone for the Coupe, but available on the sedan: Audio system, AM/FM stereo with CD/DVD player, MP3 playback and Bose 5.1 Cabin Surround Sound 10-speaker system with Radio Data System (RDS), 40GB Hard Drive Device (HDD), USB and audio connectivity with steering wheel controls.
The specs on the Cadillac website indicate that "Auxilliary Audio Input Jacks" are not available on the base '11 Coupe. I'm not sure if this is USB or if you only get the 3.5mm jack that connects to the headphone output of your MP3 player / iPod. I'm still somewhat confused as well...