He was there to tell his story, share with others how to create viral videos online and also to give them a few lessons on how to dance to Dubstep, which is a type of electronic dance music, which originated in South London, United Kingdom.
Some Broadway musicals conclude with a de facto all-theater dance party that forces the audience into a standing ovation (which they'd give anyway because that's just apparently standard now).
In Liverpool, the nightclub Cream is hosting adance party with Fat Boy Slim and Pete Tong while The Christians and Echo and the Bunnymen givea free concert in the city.