I've installed the RC-1 version on a spare hard disk partition. It seems to work very well on my rather old computer that doesn't have very good specifications by today's standards. I will be quite happy to upgrade to it when it's time to get a new computer (keeping XP until then).
As I read it at present, the Linux based Google Chrome OS will be, more or less, only a way of running the Chrome browser. This will access online applications for doing the jobs traditionally done with programs installed on the computer (word processing etc.). Files perhaps stored online too.
If that is the case, I'd be worried about what happens when the Internet slows to a crawl in times of heavy traffic, or when the connection drops altogether. At least with applications installed on the computer, it's possible to get on with something else at times like that.