I've had a lot of questions from SBSCers about Action Pack downgrade rights - we've had some guidance from Corp around this and it looks like you can stay on XP if you want to!
See the official message from Corp:
“We received several communications from our Action Pack subscribers, in which they expressed concerns regarding the removal of Windows XP from the Action Pack and the replacement with Windows Vista. In order to avoid confusion, we would like to clarify the requirements of the program.
In accordance with the Microsoft Action Pack Subscription (MAPS) agreement and the program guide, Partners are encouraged (but not required) to upgrade to the most recent version of any product included in the MAPS kit within six months. To the extent you have certain constraints that prevent you from upgrading your systems to Windows Vista, you may keep your XP licenses.
We believe that Windows Vista is an incredible value for your business and your customers’ business, and we truly hope that you will chose to upgrade and experience this new product.”