A term often used by people in North America to describe the middle class or Recieved Pronounciation accent featured on American television and cinema. Its used by the sorts of people who represent Britain abroad in the UK like Tony Blair or Hugh Grant.
This accent is probably spoken by a small minority of Britons, and whenever the topic of British accents comes up theres always somebody from outside the south of England who praises the accents of the Midlands or the North, however these accents have no credibility outside their own regions and
everybody knows it.
Context in American cullture:
The 'bad guy' in American entertainment very often has a british accent like the
X Men villain played by Ian McKellan or many of the characters portrayed by Anthony Hopkins. In recent years however, this accent has been seen by
American girls as 'cute' when sported by persons like Jude Law, Orlando Bloom or Kiera Knightly. Since this culture emerged it has been exploited endlessly by lonely British private school boys who wish to use their accents to get laid, most notably seen in Love Actually where the character Colin ends up in bed with Elisha Cuthbert and other
American girls.