If you don't get on with Unity you can switch back to the Gnome
desktop - when logging in, look on the bottom of the screen for the
option to switch desktop environment.

Ubuntu 11.10 is set to remove this option to switch away from Unity
but is supposed to add back some of the functionality of the previous
desktops. Given the howls of protest about Unity I hope there's more
than a smattering of previous desktops !!

Personally I think the Unity interface is great for the basic user who
only wants to do a few things on-line ( e-mail / Facebook / Web
Surfing etc... ) but the advanced user has lost a tad too much !!! I
know I for one would not wish to permanently lose multiple desktops so
I hope that gets put back in.