According to that Wikipedia article, I should be getting Anglia (East). My SD is indeed Anglia but my HD is Meridian! I've just retuned too.
If you look closely you'll see that Meridian is the correct "incorrect" region for your area. Hopefully things will change sometime next year when the Beeb introduces HD regions for BBC1. This may have a knock on effect for all ITV HD regions.
Yes, you're right. Most annoying! It's bizarre that my transmitter is Sudbury in Suffolk but my news on HD isn't for Suffolk!