Yes, it is possible to essentially get the Windows 7 upgrade for free. You can now buy a ‘pre-order’ upgrade of Windows 7 premium for less than half price at for $49.99. When the deal expires it will cost $119.
The trick is this, just buy two copies now. Then when it starts shipping (October 22, 2009), sell your extra copy on ebay, craigs list or whatever. Of course you can’t sell it for the $119 list, but sure you could get $100 bucks. Right now, upgrade copies of Vista go for $100 on ebay, so surely you can get the same soon after the product is released.
About your only cost is the time value of the extra $50.
Ok, you can call me a cheapskate now.. 🙂