The firm already has 800W and 1000W units almost ready and did demonstrate those at Computex but we learned that they won't be the last of them for the 2006.
We also learned that this PSU will have four lanes and some incredible number of Amps per power lane and it should cost around $/250 at launch date.
This is exactly what you might need to run two of the upcoming G80 or R600 cards, as we heard that the power consumption of at least one of them aims to be ridiculous. It seems that people do not care about the power bill only the performance and those two cards will get you on top of the pile.
Remember now, it is possible to run four cards in Quad SLI and Quad Crossfire should not be far away either. That is the answer to the question, 'Why should I need 1200W at all?' ยต