I hate to say it, but it's a computer. Think of it like this....
You buy a Windows XP Operating System. You don't install it for a month. Guess what, Microsoft came out with a bunch of updates in the last month, and you need to update before you use the OS.
GM probably came out with a new version of the ECM or something since your Diablosport was programmed.
1100, Preliminary order accepted 04/27/2009
6000, Delivered to the customer 07/23/2009 - 3 Months (worth the wait!!)