Apparently they're still checking to see if it'll work on one of my computers, (even though it's already running 8.1 which has the same requirements).
(see attachment in previous post)
And I really doubt it's going to install on the other, (my old netbook), but I think I'll force the issue somewhat by grabbing the ISO 
Just clicked on the SysTray icon on the netbook, (that wouldn't install the previews), and it tells me that "This PC is compatible."
Time for some fun and games.
-4wd
And please tell us! -TaoPhoenix
I was a little skeptical about whether it would work given the lack of success with the Preview builds on the netbook ... but MS have come through.
Upgrade from Win8.1Pro to Win10Pro via flash drive, (which has x86/x64 versions on it), took about 90-120 minutes and it resulted in a fully activated Win10Pro x86 installation. Only thing missing seemed to be the Intel 950 graphics driver but going into Device Manager and telling it to update, retrieved it from the internet.
Apart from a couple of programs related to Windows Phone, this was a pretty stock Win8.1Pro installation before upgrading.
Told it to Defer Upgrades and Notify to Restart so I'll see what it does about that.
So, on the netbook: painless upgrade
Next will be my 24/7 TV recorder/downloader/fax computer, also x86, where they're still "validating" the upgrade. If that goes OK, I might bite the bullet and do the wife's machine

I think I'll write my will while I still have arms and legs.