There's an issue with the 08's, two pcm's came in 08's... a Delphi one and an AC Delco one. Cars with the Delphi pcm are tunable, cars with the AC Delco pcm are not, and the two pcm's are not interchangable. The AC Delco pcm wont program, last he spoke to me, Will couldnt even read them correctly.
He sent me a Delphi one and it wouldnt even start my car, he confirmed it by putting an AC Delco pcm in his 04 (stock Delphi), and that wouldnt start his car.
The last I spoke to him, he told me he was waiting for a pin-out diagram from a GM tech friend, so he could work on building something to read the pcms, and then HOPEFULLY being able to go on to program them.
That was in like June, though... so Im starting to become curious about any progress (or lack thereof) and I see Omega is too...
'07 and earlier are all Delphi, and fine, though.