Have your original disk?
I would think that as long as you have you original Win XP, Vista, or 7 disc and key, all you would do is to uninstall 8 and re-install the older system. If you don't have the older Windows disk and / or key when you do the upgrade, you're most likely stuck. I seriously doubt that they would supply an older version for downgrade, with this being a "special offer". If you buy an oem computer with Win 8 and the masses are screaming that they hate it, Microsoft may offer a similar downgrade to 7 as they did in the past with others.
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