And yes, licensing is a problem for another day. The UK's gambling laws are complicated and vague, especially when online businesses come into play (it all seems like an after thought, as always). I think we've got that one covered though.
Basically unless you're a charity you'll need to be licensed.
http://www.gamblingcommission.gov.uk/gambling_sectors/remote...
Do I need a licence if I am based abroad?
You do not need a licence from us to run a remote gambling service if all of your
remote gambling equipment is located outside Great Britain.
If you are based abroad and want to advertise your gambling services in Great
Britain, you must be based in a whitelisted country or a country mentioned
in the Gambling Act 2005.
That being said, it's still probably a good idea to get a license.