Windows 7 Pre-Order from Amazon.co.uk

Amazon has Windows 7 on Pre order as you may know. I have already pre ordered the Pro version for £89 (price went up now) but today i saw this:

"Customers who buy an eligible copy of Windows Vista from Amazon.co.uk between 26th June and 15th October 2009 [ame="http://www.amazon.co.uk/gp/feature.html/ref=amb_link_84386313_1?ie=UTF8&docId=1000321063&pf_rd_m=A3P5ROKL5A1OLE&pf_rd_s=special-node-offers-3&pf_rd_r=1ZMDJ1T9KQJ22XM47DXW&pf_rd_t=201&pf_rd_p=470482053&pf_rd_i=B002DUCMTC"]are eligible for a free copy of the equivalent version of Windows 7[/ame] when it is launched. Click for details."

Now if you read closely you'll see that the equivalents for Windows 7 Ulti are:

• Windows Vista, Ultimate Edition with Service Pack 1
• [ame="http://www.amazon.co.uk/Windows-Ultimate-Service-Upgrade-Version/dp/B0013O98SW/ref=amb_link_84355233_11?pf_rd_m=A3P5ROKL5A1OLE&pf_rd_s=center-2&pf_rd_r=06RTA3J57S6S8KYPDDZV&pf_rd_t=1401&pf_rd_p=470412993&pf_rd_i=1000321063"]Windows Vista, Ultimate Edition with Service Pack 1, Upgrade Version[/ame]

According to amazon.co.uk again, if i buy Vista Ulti today (full) that would cost me £166.53 and if i buy the upgrade version of Vista Ulti that's £151.46.

As you know Windows 7 E Ultimate in Europe comes FULL (meaning no upgrade package available and also that's stated on amazon) so that means i can buy the upgrade version of Vista Ulti and on Oct 22th amazon.co.uk will send me the FULL version of Windows 7 Ultimate? Or there's a catch?

What do you guys think?

Firstly, the only difference between 'upgrade' and 'full' versions is that with the 'upgrade' version you need a prior installation or DVD to install. (There are even ways round that.)
Secondly, if the free upgrade to 7 for Vista buyers is anything like what I went through with XP and Vista then I wouldn't bother. It will almost certainly be done by agents of MS through a voucher scheme, and last time it took quite a few months after Vista was released for the DVD to be delivered.