I think it's a step in the right direction... (Score 1)

For too long motherboard manufacturers have been getting away with incomplete and buggy ACPI implementations. Forcing the issue with those manufacturers who need XP certification given the market they're pitching to, can only be a good thing surely? Having to have ACPI enabled on the board means that there can be no 'just turn off ACPI' cop out from vendors when things go pear shaped.