There's been quite a bit of interest in Aura, the display manager for Chromium OS. Its simple, sleek, and very very beautiful. So obviously there's been quite a bit of interest in porting it to other Linux distros and using it as a normal display manager. Unfortunately, its not very simple and hasn't really been done. Well actually it had been done, but not so many people notice it. In fact its running on Mac OS, Windows, Android, iOS, and most Linux distros. In fact if your using the chrome browser now (67% of my readers are) then your looking at aura. Aura is used to draw pretty much the whole chrome window including widgets. And if your using chrome in windows 8 metro mode then you should also see the rest of aura that you see on chrome is like the bottom bar and launcher. So, seems pretty simple to get aura working as a full display manager on Linux. I did it on Ubuntu 12.04. All you have to do is create an .xinitrc file, and in the exec section where you'd normally put something like 'gnome-session' you put the binary executable for the chrome browser, followed by all the handles you want to run it with. '--login-manager' is recommended its pretty self explanatory. Then if you change to a different vty, then kill lightdm with 'sudo service lightdm stop' and start X with chrome with startx then it should boot into your nice shiny aura interface. Bingo.
I know this post might be hard to follow its not my best but I haven't slept and I'm still working on this. Hopefully I'll update later.