From the press release entitled Industry Testing of Windows Vista Release Candidate 1 Begins we learn

Microsoft Announces Estimated Retail Pricing for All Windows Vista Editions

With Windows XP, customers often had to make tradeoffs in features and functionality as the Windows XP editions were aligned with specific hardware types. With Windows Vista, customers now have the ability to make choices between editions based on the valuable features they desire, which are now available as standard features of mainstream editions. For example, 64-bit support and Tablet PC and touch technology are standard features of the Home Premium and Business editions.

Pricing information for all Windows Vista editions is available online, along with additional information on the various editions of Windows Vista.

It looks like my next choice of operating system will have a suggested retail price for full package product of $399.00 and a suggested upgrade retail price of $259.00. Given that I'm running Windows Server 2003 at home it looks like I'll be paying the higher price.