"One of the best things about Windows Vista's new packaging is the fact that all retail versions of the OS are on one disc. If you have one copy of Vista, you have the code for almost all of the other versions.
That's the driving force behind Anytime Upgrade, and it's also the reason why Microsoft is now trying to entice consumers into buying discounted licenses. This past week the company announced the Windows Vista Additional License program, which provides discounts to customers who have already purchased either a retail or an OEM edition of Windows Vista. The program was announced by Nick White, Microsoft product manager. According to White, the offer has been available for several weeks, although unannounced, and it will be made available in Europe, Asia and the Middle East early next week."
The good news is that it is a discount, and hopefully there will be more to come.