I would say Craig was much better than Brosnan.....Brosnan wud never have been able to pull this off......The role of gritty man just does not suit him....Sure brosnan looks more suave, Craig is comparable to him.....In the action sequences he beats all the other bonds.....
Also in this movie we really feel for the hero......Also as nikhil mentioned, in most scenes we already know the outcome but the movie still manages to keep us strapped to edge of the seat.....