@Bandana Boyz -- My home machines have various W7 versions of Home Premium, Pro, and Ultimate.
The only difference between Pro and Ultimate I can see here:
http://www.microsoft.com/windows/window ... fault.aspx
is Ultimate has BitLocker and access to 35 languages --
I spent 45 minutes on the phone with Microsoft yesterday being passed from customer service to activation to customer service to activation tech support

I upgraded XPPro to W7 Pro on my latest X60s with a retail upgrade version and apparently did something wrong this time because the activation screen blocked activation due to a 'clean install' error (as opposed to 'upgrade')
I get confused each time I upgrade -- each machine has a different story -- several were newer machines when W7 came out, and Lenovo provided disks to upgrade from Vista to W7 -- that was awhile ago, so I don't remember details except that it was pretty straight forword and activated online.
I upgraded some of my other machines this past year using the W7 Home Premium Family Pack, and I think all activated online except one -- which was a quick phone call with automated phone activation.
I upgraded my husband's X61s just last week (tried the Home Premium Family Version, which I forgot would not work because he had Vista Business -- so I purchased download of W7 Ultimate because I already had a disk from my kid's T60) -- that upgrade activated easily online --
So yesterday's latest upgrade from XPPro to W7 Pro was frustrating not because I had to call, but because it took sooooooooooooo long and four transfers before Microsoft approved the install --
Not sure if you 'need' BitLocker/+35 lanugages access -- if not, I would want the Recovery CD's that match my original install -- you never know when Microsoft will tell you a reinstall is not valid --