@OP - Reasonable prediction, I think your numbers for the 360 are a little low personally but not too far off. I would have gone for a 4-6 million range if I had to put a figure out there, mainly because I think it will be about 5 million in January, with the 360 big price drive coming next year around September to bring the gap back up from the 4 million it will be down to by then.
Will be impressed if you're right though!