Somehow I suspect Google's always connected to the mothership mentality will lead naturally to Chrome OS being intended to ship with netbooks equipped with 3G cards and a contract. Just like Android only on bigger displays and with a keyboard. So expect the same vendor locks.
I'll be shocked if you can get to root on one, to say nothing of actually loading a home rolled image or unsigned app. Like the gPhone we might get an option to buy a 'devel' version.