Why not have both?
An Android tablet that also has Chrome OS on it.
You plug the tablet into a dock and you have a complete operating system more suited to a desktop environment.

People are already doing it with Ubuntu, this way you get it all from a single source so have the potential for better integration.

I would love to see this on the new google tablet when it arrives.

Wow I never knew that England was an island.
If the GDP of England was $2.2 trillion what was the GDP of Scotland, Wales and Northern Ireland?

Or are you one of those people who doesn't understand the difference between England and the UK?

You are correct that it states "a reasonable amount of time" and the interpretation of a reasonable amount of time is left up to the interested parties to decide.
The argument that PC hardware is reasonably expected to last a minimum of 3 years is easy to establish however as that is the time period that all companies I have ever worked at have used as the depreciation period.

I would say it is reasonable to expect things like Televisions, Washing Machines, Dishwashers etc to last a minimum of 5 years.

Nah. Usually just older.