Yesterday I spent a bit of time reading a thread on Arch Linux ARM forum about their issues with Samsung ARM Chromebook. And found interesting information there.
Why Arch Linux ARM? Because they posted guide for replacing original U-Boot with normal one. I plan to make some modifications to my Chromebook (once it return from service as I want my speakers back) and this will be one of them (other will be serial ports).
If someone want to try this distribution then Craig Errington describes on his blog how to install XFCE. I did not used it and do not plan to but will check for tweaks and hints to get my Ubuntu experience better.
So if you play with running other distributions than ChromeOS on you Chromebook then check their forum — maybe you will find something useful as well.