Djokovic is more offensive than Federer or Nadal but could be considered defensive when facing someone like Del Potro.
Love it when Djokovic hits down the line half volley winners off both forehand and backhand wings. He does it generally when he has nothing to lose. I remember his Montreal match against Federer in 2010. He was hitting magical winners off both wings late in the 3rd set and Federer was lucky to win that match. Federer himself said in the interview that there was nothing he could do during periods of the match. Djokovic's forehand has improved ALOT. It has become more of a weapon and he is a well rounded player now
. The right mix of defense and offense which is essential to dominate like Dkojo has done so remarkably well in 2011. Hats off to a historical season!