Microsoft would like you to know Windows XP Mode, the OS virtualization feature built into Windows 7 Ultimate, is now available to test drive on the RC or RTM versions of the new operating system. For those that've been thinking about grabbing the Ultimate version (which is bundled with it) versus Home Premium or Professional (the former can't use it, the latter can download and install it), this should help you make up your mind. Note an additional 1GB of RAM, 15 GB of hard drive space, and a hardware virtualization-capable CPU are needed here.

Microsoft reminds the feature won't be necessary for most of us, it simply provides “last mile” compatibility technology for special cases regarding applications, particularly for business users.

Since the beta version, they've made several important changes based on feedback. Here's what you get:

• You can now attach USB devices to Windows XP Mode applications directly from the Windows 7 task-bar. This means your USB devices, such as printers and flash drives, are available to applications running in Windows XP Mode, without the need to go into full screen mode.
• You can now access Windows XP Mode applications with a “jump-list”. Right click on the Windows XP Mode applications from the Windows 7 task bar to select and open most recently used files.
• You now have the flexibility of customizing where Windows XP Mode differencing disk files are stored.
• You can now disable drive sharing between Windows XP Mode and Windows 7 if you do not need that feature.
• The initial setup now includes a new user tutorial about how to use Windows XP Mode.

 The XP Mode release candidate can be downloaded here.