Source: http://bishopbjj.com/ these guys did a series of excellent articles where they desconstructed the 2012 Pan Am. This is the result of their research.
They have a whole series of articles with statistics.
They analysed what were the most successful techniques from the 2012 Pan Ams black belt matches. The numbers speak for themselves:
The Best Butterfly Player In The World Shows The Exact Techniques He Used To Win The ADCC Trials With Over 50 fighters In His Bracket - In His First Ever No Gi Competition.