Numix FlatStudio has been updated and now supports GTK 3.14, 3.12 And Xubuntu.
Source Numix FlatStudio: Numix FlatStudio Gnomelook.
4 variations to choose from.
Dark, Flat Studio,Red, Turquios.
You can download Numix FlatStudio directly from the Ubuntu Alive Dropbox below.
The Icons used are Numix Circle Flat and you can install them from the PPA Below.
sudo apt-add-repository ppa:numix/ppa
sudo apt-get update
sudo apt-get install numix-icon-theme-circle
The Wallpaper used is called Flat Numa Mountain-7 By Charlie Henson and can be directly downloaded from DeviantArt below.
That's it please enjoy this amazing theme..