If you want to step-up from any 8800 card - no matter the manufacturer - to a Geforce 8800 Ultra, it won't be as easy as you might think.
EVGA has total of 40 cards for this program and half of them will go to North America and Canada and the other half is for the whole of Europe.
If you are already an EVGA customer who has an 8800 card, the upgrade will get easier and the company will have more cards for you. Be sure that you don't wait too long though.
EVGA wants to capture customers and it can and it probably will be able to resell the cards it gets from the step-up or Nvidia will take them back. Anyway they have some special sensitive deal that no one knows about.
You can step-up to a new one here.