The reverse situation from what you will normally read about people switching operating systems.
Gnome 3 and Ubuntu: Like peanut butter and chocolate.
If you're going to have a computer on all the time, it may as well be computing.
Thumbs up for Fedora 17. Thumbs down for 18.
To say Fedora 18 is a little rough around the edges is being kind. It looks good, but the functionality is not there.