Did you upgrade from 32 bit to 64 bit? What version of Windows were you running before?
Don't forget Sonar will be supplying a patch but I'm not sure exactly what that will achieve.
To be honest this is all generally to be expected, but there's nothing wrong posting a reminder for people I guess. If you ran the upgrade advisor it should tell you about
most of the applications that won't work. It won't tell you about the plugins though. As with all operating system upgrades YOU MUST CHECK to see if you're software works with Windows 8 before you upgrade otherwise you are just jumping blindly into the deep end (although some of us like swimming ;).
I also recommend creating a new bootable partition for Windows 8 and installing it clean next to your previous installation, that way you can use your old OS and slowly build up a workable Windows 8 environment side by side.
And always backup before any upgrade so you can revert back!