I use the Samsung chromebook for writing / browsing / mail / fb / movies; I find it so much more pleasant than a tablet. And I switch on crouton if I want to do development or run emulators (my favorite ones run fine on it which allows me to play games). Besides actually building / publishing apps, I hardly touch my MBP anymore. I don't see why the plastic etc is a problem; it's nice and light, cheap (almost impulse) and it can run almost everything I want/need.

Even if crouton did not exist, I would use it for browsing/writing over a tablet or a heavier, more expensive computer.