There are perfectly legal ways to watch these shows in the UK. One way is to watch them in the house of someone serving in the US military over here, for example someone in the USAF living at RAF Mildenhall, RAF Croughton, RAF Fairford etc. They have US satellite TV on all these bases, and in the on/off base housing.
I think we should be allowed to discuss these shows, though I agree that people watching the UK shows should not have their enjoyment spoiled. Seperate threads would be the best way, I'm British and UK based but I watch american TV. I have no idea what has aired in the UK yet as I don't have Sky/Virgin, so I'd have no idea what to put spoiler tags around and what not to.