i saw this on the net
But Vista Ultimate is different. Under the Additional Terms section for that OS, the license reads:
You may use the software installed on the licensed device within a virtual (or otherwise emulated) hardware system on the licensed device.
In other words, if you are running a licensed copy of Vista Ultimate, you can load another copy of that same OS, using the same product key, in a virtual machine on that same computer (the "licensed device"). This license gives Vista Ultimate users a right they wouldn't have with any previous version of Windows. (The Vista Enterprise license will reportedly be even more generous, giving users the right to run up to four virtual copies on the licensed machine. There's no indication of what virtualization rights will be included with Vista Business.)
In this case, at least, Microsoft deserves congratulations, not criticism, for addressing the issue of virtualization in a way that makes sense for its most tech-savvy customers.