I did get an email back from of the local GMC/Chevy dealers (Ramey) and the guy there said they will only stock diesels with certain minimum specs and if I wanted anything less they could order one, but it wouldn't be that much cheaper.
I know my '04 avalanche was assembled in Mexico, both of my '04 3500's 1 vortex/1 duramax are both USA. I just haven't spent enough time looking under the body outside of engines and transmissions. I do know a couple of guys who have '07 Dodges w/Cummins and have had issues with the turbos, but other than that. I know the history of the Ford's and the 6.0 but I haven't heard anyone say anything about the new engines.