Well, I installed the windows 8 upgrade and my new ssd yesterday... wasn't as easy as I was expecting though (I started sweating when I switched to AHCI mode in the bios while in 7 & it then wouldn't start... then I found out that I couldn't clone my win7 partition with the tool intel provided - only allows full disk cloning... then the ssd stopped being recognized half way though the win8 install - good times
As for Windows 8 itself... It's a pretty strange OS
lots of improvements in the UI (very clean & crisp menus, etc), speed & the lack of start button isn't as bad as most people are saying (just stick your stuff in the metro area)...
but some strange choices (almost all of the metro apps you start with are complete sh!t - take the message tile for example : if you've got a gmail ccount, it doesn't nest the messages, so it's wildly disorganized... & the picture app - you can't pick specific folders apparently)...
and some things are nuts (want to get rid of the log-in screen if you don't need multiple accounts ? or of the start page ? good luck finding out how to do that without looking it up
still, if you can get your head around it, the advantages probably outweigh the problems (especially if some metro apps that are actually useful start being provided)