I?m very pleased to let you know you this morning (or afternoon, or evening, depending on where you are when you read this) that the Windows division has revised the retail license terms for Windows Vista in a significant way. Namely, the terms regarding license-to-device assignment of the retail product (including Home Basic, Home Premium, Business and Ultimate) now read as follows:

You may uninstall the software and install it on another device for your use. You may not do so to share this license between devices.

Windows Vista Blog