32 bit to 64 bit upgrade paths

I really love Microsoft Vista 32 bit. I really, really do. However, one thing I find rather terrible on Microsoft's upgrade advisor website is lack of clarity to upgrade from 32 bit operating system (O/S) to 64 bit O/S. In fact I decided to pretend I was a customer interested in such an upgrade and decided to browse their website. It is quite discouraging that I was unable to find clear information. Perhaps even more frustrating is to perform an internet search engine for 32 to 64 bit O/S upgrade information and find almost nothing worth mentioning. There SHOULD be an upgrade from 32 bit O/S to 64 bit O/S somewhere in the pipeline especially for all of those hardcore gamers out there who want to pop in 4gb or more of memory. Many customers are not aware of the 4gb memory limit in the 32 bit Microsoft Vista 32 operating system. I would really like Microsoft to seriously consider an upgrade path from a 32 bit operating system such as Microsoft Vista Premium 32 bit to Microsoft Vista Premium 64 bit at a much lower price upgrade.