I agree, I can't really see Microsoft trying to replace Windows 7 before 2013. It has been a market success - several businesses and some governmental agencies in my area are making the switch to Windows 7 in the next two months. Word of mouth has been miles beyond the wom for Vista.
What I do see is the incorporation of native SATA 6Gb/s and USB 3.0 drivers in a future service pack. I had hoped it would be SP1, but as the adoption has been slow and it nears final testing stages, I hope they are in SP2. AMD has already added SATA 6Gb/s and USB3 to many of its boards and Intel is putting out its first in the coming month.