Linux Mint 14 is of course a nice imitation of the Windows XP desktop. Zorin 6.1 again is a nice imitation of the Windows 7 desktop. Mint Mate is for the Ultra Conservatives which somewhere between 2004 and 2010 picked up the Gnome 2 desktop and want to stay with that desktop for the rest of their lives.
The real stuff is of course Ubuntu and Unity, which will allow to serve all screen sizes from large TVs till the small smart phones. All will have the same look and feel. Even the HUD starts to make sense now for the first time, because it will be coupled with speech recognition.
The old ages of computing brought the CLI, afterwards we had the middle ages with desktops like XP (Mint) or Win 7 (Zorin) or Gnome 2 (Mate), but now since yesterday we can see the future of computing Unity and it rocks