Just to follow that up: in the UK "England and Wales" is often treated as one entity, for example for laws and statistics, and is included in ISO 3166-2 as GB-EAW (or UK-EAW) England and Wales. I think this is quite an unusual case but is there any chance of this being reflected in WOEIDs? Without it, I can't see a coherent (and non-hacky) way of doing some things i'm trying to do.
At the moment, SELECT * FROM geo.places WHERE text = "England and Wales" returns the town of Wales in South Yorkshire, England — which is lovely to know about but no damn use!