In the last of the BronyCon 2014 Grand Galloping videos Fluttershy and Rainbow Dash come out on stage to announce the rules of the Battle of the Waltz's competition.
Sorry after this I decided to leave since it was really late and I had to drive home the following afternoon.
Part 1
https://www.youtube.com/watch?v=f9jEUQDVQM0
Part 2
https://www.youtube.com/watch?v=EcNQSfqaCvE
Part 3
https://www.youtube.com/watch?v=Qpusa30jaHc

BronyCons YouTube Channel
https://www.youtube.com/user/BroNYCon