The Upgrade for WIndows 7 is available on Amazon.com for Pre-Order and it will only cost you $49.99 for Home Premium a savings of $70 from the suggested $120 or $99.99 a savings of $100 for Professional.
From my understanding the upgrades available for pre-order on Amazon.com are for both 32bit and 64bit versions of Vista. So if you feel like ordering your copy upgrade of Windows 7 now visit Amazon.com.
You may also notice that the Microsoft store is down as well, we can only assume it is being updated. (may be live and updated when you read this post)
Update 2:07 am EST:
Microsoft has updated their store, and are offering Windows 7 at 50 and 58% off. Visit the Microsoft Windows 7 Section here.