Is the main market for chrome books (a) people who want to install Linux and other OSes on them and (b) people who do not want the hassle of adminning a traditional OS?
the theoretical market for chromebooks is people who only want a computer for facebook and email and want to buy something simple and cheap.
in practice, i think the market is just nerds who want to play with a chromebook because it's new and cool. i appreciate what google is trying to do with chromeOS, and i think it's a good idea, but they have failed miserably at marketing it to non-techies.
If it's secure, easy to use and browses "the Facebook" I could see giving them to a relative and saivng a fair amount of tech support time. Granted an iPad fills the same nitch but it costs twice as much.
It depends on whether you want a keyboard, too, or not. A keyboard costs extra money for iPad, and it's not a very elegant solution either. I'd much prefer an Asus Transformer if I were to choose a tablet over a Chromebook.