Microsoft’s Edition Soup ↦

Walt Mossberg explains how to upgrade to Windows 7:

There are limitations on which current Vista machines can be directly upgraded to the various versions of Windows 7. In general, you can only upgrade your current version of Vista to the comparable version of Windows 7. For instance, Vista Home Premium can only be upgraded to Windows 7 Home Premium and Vista Business can only be upgraded to Windows 7 Professional. This rule has two exceptions. Any flavor of Vista except Starter can be upgraded to Windows 7 Ultimate, if you care to spend the extra money. And Vista Home Basic can be upgraded to Windows 7 Home Premium. […]

However, there’s another complication. For each of the three main consumer versions of Windows 7, there are actually two editions. One is meant for PCs with standard processors, called 32-bit processors, and the other for PCs that sport newer processors called 64-bit processors. The 32-bit version of Windows can recognize only 3 gigabytes of memory, but the 64-bit version can use much, much more. […] The problem is that you cannot directly upgrade 32-bit Vista to 64-bit Windows 7, or vice versa. So that adds another layer of complexity to the upgrade process.

Thanks, Microsoft, for not making technology any more intimidating than it needs to be for the non-technical. Oh, wait.