One of the huge advantages of the Chrome OS is that it puts almost everything on the cloud. This gives you the flexibility to access your data from almost anywhere that has an internet connection, as well as a safer place to leave your data in case of some kind of individual accident.
What kind of accidents? Well, anything could happen. The Google Chrome OS Cr-48 Notebook appears to be very much a notebook like many others, and it can be destroyed just like all the notebooks before it. The key difference is that the physical destruction of the Chrome OS Notebook won't affect your data.