Ok, I have tried Windows 7 and I like it, so I want to start using it, don't want to wait another 2,5 months while the final version is already there. I tried the OEM trick and it works fine, but I don't want to go that way. I have an official version of Vista (actually a few) so I am eligible for an update. 7600 seems to be the final build, so. Now how can I install this as an update to my Vista, and keep using it until oct 22 when I can buy a license without installing Win 7 all over again? Is re-arming the only option, or there a trail key I could replace with an official key later?