There is a thread in Tech Log that goes into some detail regarding the different recommended methods for handling an overspeed at altitude. It would appear that Boeing & Airbus are quite different in their recommendations, with Airbus recommending power to idle first & Boeing recommending the use of speed brake first & power not below 60% N1 (B737NG).
http://www.pprune.org/tech-log/53879...overspeed.html