Though the movie is a good entertainer, Ajith acting is not very good in this movie(most of the times he walks walks and walks. thats all). I don’t see any energy in Ajith acting. His character is supposed to be charming and energitic but he doesn’t show anything in his face. Even in the song "my name is billa", he doesn’t show any energy(He just walks and walks but this time in white suit instead of black). Prabhu and Rahuman have done their roles well.
Nayanthara character is not well characterized in the movie(just wearing some hollywood style suits and having guns -> but she does nothing with those in the movie. just carrying them as though she is a model).
The major flop is the handling of the "pen drive" in the movie. In the older movie(rajinikanth version) it is a diary and they tried to handle the "pen drive" concept just like diary which is where it is a complete logical flop. I don’t know why the climax is mostly revolving around getting the just the pen drive and not the content in it(which ajith gave to police)? Though the pen drive content can easily copied to the computer, I don’t know why police and gang everyone is interested in getting the pen drive back instead of trying to delete the content copied from the pen drive(complete logical flop:D) May be this concept is difficult to understand by those who doesn’t know much about computer usage.
However the movie is fast moving and the movie team has somewhat succeeded in their effort to bring the movie in hollywood style.