Vista and XP users will need to pony up $119.99, $199.99, or $219.99 on October 22 to score their Windows 7 Home Premium, Professional, or Ultimate upgrade, and those of you who want a full retail disc will need to roll up with $199.99, $299.99, or $319.99 respectively. It’s not quite that simple, though: starting tomorrow, June 26, you’ll be able to pre-order upgrades at much cheaper prices — $49.99 for Home Premium and $99.99 for Professional..

Link:
http://www.engadget.com/…

In case you don’t know the difference between the versions check this out:
http://www.veign.com/blog/2009/02/windows-7-versions.html

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