Hi Marc
I'm not aware of a specific group that exists to this end.
Both I and my predecessor on OOo have concentrated on getting the UI and HC2 translated into British English for en-GB locale users and then getting this QAed and distributed such that it is the variant naturally picked up by those users. I'm a bit concerned with LO that we haven't got this sussed yet as 'English' users will typically pick up a en-US installer and not even bother (or know) to look for a language pack.
I've not bothered with translated web pages for en-GB as the differences I've found with OOo, say, are trivial enough to pass over.
Anyone from en-ZA wish to comment?
Cheers
Stuart