Now you can have a finely tuned native Linux OS that's designed for Chromebooks. You can always dual boot it with ChromeOS to solve the problem of guests using it.
I actually just ordered a Chromebook yesterday. Can't wait until it arrives this week and set it up with Gallium.
There are 101 (really) Chromebook models, past and present. 33 are ARM, but GalliumOS supports almost all of the remaining 68.
The main issue with desktop Linux on ARM Chromebooks (that I encountered) is HW acceleration. GLES support is sketchy to nonexistent among the current crop of window managers. I am hopeful that some of the work the Pyra team is doing to bring a standard accelerated desktop to a mobile device can be reused on the Chromebook - I've already had some success with GLshim, which was developed for the Pandora.