I upgraded my work laptop from FC11 to FC12 yesterday using the “preupgrade” tool. It was pretty simple, though it took a lot longer than I expected. There was some funkiness with my screen going crazy after the upgrade – my external monitor and the laptop’s LCD both did this crazy wavy-line thing. I tried changing the refresh rate, running system-config-display, nothing worked. I found a post that suggested passing “nomodeset” to the kernel boot options – that solved it. Yay!
The other problem I had was reinstalling VMware Workstation – I couldn’t. I got this error: /tmp/vmware-root/modules/vmnet-only/vnetUserListener.c:240: error: ‘TASK_INTERRUPTIBLE’ … etc. I ended up having to edit the vmplayer source files directly (!!!) to get them to compile – instructions found here
So far FC12 seems exactly like FC11. But that’s fine – I only upgraded because I didn’t want to be on a dead-end version once FC13 is released.
Evan Hoffman's Blog 