I've been test driving the F15 alpha/beta versions since January, switching to F14 for work purposes and although Gnome 3 is "different" it's not as unwieldy as Unity and I am pretty comfortable with it now.
Three hints to make the transition a little easier:
1) Install the Avant Window Manager from the package manager.
2) Install Fedora Plus (previously autoten) to assist with missing codecs, flash plugin etc
http://www.dnmouse.org/autoten/fedoraplus-autoten.html
3) Read the following article for a rough guide on creating a new program launcher to add shortcuts to the applications screen
http://bloggezmoy.com/?p=449 (it's advice from a ArchLinux user but the basics are covered).
BTW: I think both Unity & Gnome 3 are best suited for large16:9 displays ( > 21"), my experience with both on a 20" 4:3 Acer LCD was not good to say the least.