It seems clear that MS have restricted somewhat the list of qualifying hardware that must be bought at the same time, to purchase an OEM Windows Vista license.
On the Scan Vista OEM description pages it says this must be 'a nonperipheral computer hardware component' and then later 'A “nonperipheral computer hardware component” means a component that will be an integral part of the fully assembled computer system on which the individual software license will be installed.'
On the Today Only page, you suggest that a DVD-ROM drive is one such qualifying component.
Can you, in the item description for Vista OEM licenses or elsewhere, publish a FULL, clear list of qualifying components? e.g. Processor, Motherboard, Hard drive, PSU, Case, DVD-ROM drive?
I think this would help people understand exactly what needs to be purchased to qualify for an OEM license. IMHO it's still a little unclear ATM.