A friend showed me this article, from Paul Thurrott, a total windows supporter. http://www.winsupersite.com/showcase/winvista_editions.asp The article describes all of the different editions of Windows Vista, and all the things each edition is capable of. A total of about 9 different versions, I think, its all a bit confusing (but hey, its windows!!). I think the article can be summed up with this quote: So, in conclusion, for Apple to dominate market share for operating systems, all they need to do is release a single version of OS X for x86. . . and people will switch because its more simple, secure and powerful than any of the dozens of Vista versions that will be offered!