Comment 14 for bug 158392

If you compare

Atolm http://lh4.ggpht.com/_1QSDkzYY2vc/TRuBDMhY0qI/AAAAAAAACjU/aeXX8nv-7XA/atolm_by_skiesofazel-d35xysb.png

The previously posted dark theme https://bugs.launchpad.net/ubuntu/+source/ubuntu-artwork/+bug/158392/+attachment/282012/+files/Captura_da_tela-2.png

and Chocolate I would say Chocolate is more Ubuntu-like. It may be too low-contrast for some screens, though.

The background used for the screenshot is here

http://www.2desktop.com/download_Ecto_Volcano_Abstract_free_quality_desktop_wallpaper_1920_1200_resolution_4744.html

I have no idea about its license so I only post a link for your information.