Using Google Chrome OS on a netbook is an excellent idea being developed by Google. It stores everything on the cloud and needs you to be connected to the internet all the time. All your stuff like Docs, music, pictures, everything is stored on the cloud rather than on your system. The concept is amazing but I would rather have a little bit on control on the system and how my data is placed. If I am not connected to the internet all the time then it would be basically useless. I prefer keeping my documents and private stuff on my system and also would like to keep some music because if I am unable to connect to the internet due to some reasons, I would just sit idle.
I would rather prefer using a light weight Linux based OS, something like Arch Linux and build it according to my needs. I could install the latest Google Chrome with web apps and have the functionality of Chrome OS, also I could use a light weight Desktop Environment like XFCE or Fluxbox to use the system when I am not connected to the internet. I would then be able to store my music, pictures, docs and couple of movies which I could use when not connected to the internet.