Well, not tomorrow. However, I believe the wheels will start coming off the Windows bus in a few years unless they start changing their strategy now. PCs are increasingly becoming service interfaces. Chromebooks are limited right now because they are uncompromisingly betting on that future. The question isn't what can your Chromebook do that your Mac or PC can't, but what can your Mac or PC do that your Chromebook can't. Every passing year, that list is going to grow shorter. Eventually, Chrome will kill Windows with convenience (and a cheaper enterprise licensing model).
Right now Chromebooks seem like little more than tablets with a keyboard. On one hand it would be nice to see more competition in the OS market, could breed innovation and lower prices. On the other hand the more fractured the OS market becomes the more compromises I'll have to make picking one device over the other or the more devices I'll want to own to get the best of all worlds. I really don't see any appeal in the Chromebook aside from it being a travel PC, maybe the future will prove me wrong. I'd bet on Linux as the free operating system of the future before ChromeOS but it's not a bet I'd really want to take. If an alternative free OS could intrench itself in China or India I think it would have a good chance to capture the future of computing.