I've been using GNOME 3 on Fedora 15 for a while now and I'm pretty pleased with it, that being said, it's far from perfect. There are several interface choices they've made that remove what I would consider obviously desirable functionality and hide it away or remove it outright.

Removing shutdown and restart from the user menu. Sure, if I hold down option or control or whatever the key is those menus appear, and of course I can also open up the shell and 'shutdown -r now' my way to freedom but the point of the menu is convenience, and that's not.

Removing the minimize button from the windows /is/ a gutsy choice, and I do respect them for it as they appear to have a good plan in place, however they do have to understand that if you are using a system with multiple monitors, which in my experience is not uncommon on Linux computers, having multiple workspaces seems redundant. Though, for me only one screen has the workspace change, and I might be more fond of them after that bug has been worked out. ((note: It is possible to bring the minimize and maximize button back, and you always can minimize and maximize by right clicking on the titlebar, but again that's not the point :p))