I have to agree with some of the recommendations regarding London and Brighton. I have spent the last 10 years living and working between London and New York City. Based back in NYC now, but spend up to 100 days a year in the UK and lived there full-time in '03 and '04.

If you want to take the "go big or go home" approach, London, of course is your choice. As another poster said, too many people spend their time in London stuck in the West End and the Soho bars. There is tons more to explore and experience in the London area and you don't have to be overwhelmed by Central London if you are looking for a feel that is a bit smaller. 20-25 mins by train can bring you to a completely different world. I spent part of my time living in Surrey, which was a very different - and enjoyable - perspective from the time I spent living in Kensington, (Central London). I tell my London friends that they are too unappreciative of their city - London is, indeed, one of the great cities of the world.

Brighton, on the other hand, is a very nice alternative. It is far enough removed from the big city, but without being in the middle of nowhere. As stated earlier, it's about 25 miles from Gatwick Airport, so it's quite easy to get off the big island for some quick EasyJet weekends. The gay scene, as stated, is there and people are tolerant. The town itself is very nice. I used to do a lot of work with American Express there and my American ex-pat colleagues who were based in Brighton always used to tell the London-based ex-pats that they didn't know what they were missing...

Good luck!