"Why might Joe be interested in changing up? Here's a subtle part of Microsoft's ploy: as the company focuses on the digital entertainment sphere over the next several years, it is going to be unveiling products and services that interact with the features of some of these OS versions but not others. Let's take an example from a shipping product. Windows Vista Home Premium will allow you to stream movies and videos to the Xbox 360. Maybe you don't have an Xbox 360, so you choose Home Basic for now. What Microsoft has put into place is an easy for you to move to the Premium or Ultimate version of the OS for any reason, whether it's to get Media Center's spotlight, new Xbox interactivity features, or some other as-of-yet unannounced product or service. You may not have an Xbox 360 right now. You may not have any desire for Media Center functionality. It's no matter. If and when you do, the OS can be upgraded on the fly."Now that Microsoft has announced there will be four different versions of Vista for home users, the question becomes how easy is it for the user to upgrade to a different version if they want more features than what's offered in their current version? Windows Anytime Upgrade is the answer. I think this could work out really nicely for consumers, assuming that that the price to upgrade isn't more than what that difference would be at retail.