There is a 15 minute flick through of the pdf version of the rules. The narrator, Charles, makes a couple of small mistakes when giving descriptions of some of the rules, but on the whole he paints a good ol' picture.
For a more detailed look at game play, there is also a longer video documenting a play-through of what seems to be the first game of G&G played by the lads. The conclusions? 'Will play again!'