Microsoft's Windows 7 pre-order is up, and in addition to Amazon, there are a number of retailers offering Home Premium and Professional at significant discounts:
Costco
Sam's Club
Best Buy
Walmart.com
Microsoft Store - Here, you can choose between packaged and download versions, by the way
Fry's Electronics
Amazon.com
Office Depot
TigerDirect.com
Office Max
NewEgg.com
Quill