It looks some of the powers-that-be at Microsoft pulled their heads out of their deep, dark, unmentionable places and loosened the restrictions on Windows Vista device transfers.
The first user of the software may reassign the license to another device one time. If you reassign the license, that other device becomes the ‘licensed device.’
You may install one copy of the software on the licensed device. You may use the software on up to two processors on that device at one time. Except as provided in the Storage and Network Use (Ultimate edition) sections below, you may not use the software on any other device.
Now, unless you’re an enthusiast who has purchased your own, non-OEM copy of Vista, this really doesn’t apply to you because it is against the terms of the license to transfer your OEM copy of Vista to a different device. I think most people fall into this camp because it’s the OEM version of Windows that comes on computers bought from Dell, HP, etc. But, if you’re a propeller head who enjoys tinkering with your machine, and you have your own non-OEM copy of Vista, then have at it.