Ubuntu has been using the Unity desktop environment for quite a while now. I was surprised to find out that they still had a standard GNOME version as well. No idea how long this has been the case, but it wouldn't matter too much since GNOME 3 and Unity are almost identical.
It looks like I'm running in greyscale mode! Except I'm not, and what's more is I couldn't set the background to a solid color as apparently that isn't an option anymore, so hopefully these shots won't take forever to load for you.
The "Activities" page, which is basically GNOME 3's version of the Dashboard. I am not a fan of these full-screen menu things, I prefer the much more traditional application/start menu.
The file manager hasn't changed much, but I don't think this is Nautilus anymore; it just refers to itself as "Files".
One thing that is very obvious, is the lack of any kind of menus. I don't think there are any real menus anymore, just this thing that appears when you right-click the application name on the top bar.