Thanks for pointing that out but I think that unless you were hiding from the internet or something, everyone in HN knows about Chrome OS. I'm talking here about a desktop OS, not a browser-mode.

I suspect Google is more interested in tying to their services rather than having the user make their own app choices. Additionally, desktop OSes require a higher level of support than Google is willing to provide (they might actually have to provide some support as opposed to now, which is apparently nil).