Well, the title says everything. I mean to clarify the confusion that lingers over the upgrade options, because of some questions that I came across on the forum and some of the users' comments to articles. You can upgrade to Windows Vista from Windows 2000, Windows XP Professional x64, Windows XP Tablet PC, Windows XP Media Center, Windows XP Home and Windows XP Professional. And that's about it. They say that one picture is worth a thousand words. In this context, the image included at the bottom illustrates the Windows Vista upgrade options.

One aspect that I want to point out is that there are indeed some limitations to the upgrade process. First off, users will find that they are unable to perform clean Vista installs with upgrade keys. But there is a way of circumventing this restriction. Read about it here.

Additionally, you will only be able to upgrade to x64 Windows Vista editions from Windows XP Professional x64. Microsoft requires users to have an x64 operating system in place in order to deploy one of the 64-bit editions of Windows Vista.

Users additionally have the possibility of upgrading from one version of Windows Vista to another on the hierarchy scale Home Basic > Home Premium > Business > Ultimate.

And of course there is the small issue of the clean install versus the in-place upgrade. An in-place-upgrade will enable users to transfer all their applications, files and settings to Windows Vista from the previous edition of Windows.

Clean Install will by no means wipe everything off your hard drive. If you choose to do so, it is your choice, and you will indeed lose all the data on the partition on which you install Windows Vista. But there is also a non-destructive way to clean install Windows Vista that moves the operating system you have in place to a Windows.old folder.