I think any conflation is quite intentional. For all practical purposes, ChromeOS will be inseparable from the devices that run it, much like the iPhone and the iPhone OS.

Google has been quite clear that ChromeOS will not be run on general-purpose hardware. ChromeOS is designed for low-cost low-power ChromeOS devices, that will be packaged more like an appliance than a traditional computer.

You might be able to force Windows or Linux onto one of these ChromeOS devices, but you'll have to hack it.