Upgrading FC6 -> F7 is not painless at all (whereas FC5 -> FC6 was a breeze). The things that needed sorting out were :

• Samba shares no longer work – not sure why. Quickest to rebuild /etc/samba/smb.conf rather than sort it out properly.
• xorg.conf file fails (causing even greeter login to fail). Probably due to wacom driver not being fully updated in the distribution
• libata complains about CDROM drive – stalling booting process.

There’s sure to be more, but that’s a flavour.