I think sometimes people confuse 'Usability' with 'a-Windows-like-gui'. Because it doesnt look and act like Windows then its not 'usable'. It is true though that a majority of computer users are more familiar with the windows way of doing things and therefore most Linux/UNIX DE's have borrowed heavily from it - but they have also added a whole lot more. Heck, I personally find Linux more usable and feature-rich than windows.
If you are on Mint 12 or Ubuntu and Gnome 3 is giving you a hard time, consider trying XFCE, LXDE (my preference) - you just might like them.
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Ndungi Kyalo
neno.co.ke ~ Your word O Lord, lights my path.