I just saw Sherlock Holmes II: A Game of Shadows, and I really enjoyed it! Unlike most people, I was very disappointed with the first one. I liked the actors, characters dynamics, etc, I just felt like the mystery aspect of the story was pretty dumb, and I definitely don't enjoy watching something with a twist and a solution that I have no way to predict. Don't get me wrong- I don't expect to be as smart as the detective in the film, but I want to feel satisfied with the conclusion, and also anticipate feeling rather frustrated in my inability to be that perceptive. But the first movie's conclusion made no sense, and there was nothing to foreshadow the ending or the way Holmes solved the case. Mark Strong was not a very believabe antagonist, either, his portrayal and his character were mediocre at best.
The second one, however, was much more convincing. First and foremost, it was hilariously entertaining and fast paced, cracking up the audience but managing to keep the plot serious and pressing as well. The 'bad guy' (Jared Harris) was perfectly creepy and very convincing. His image was fluff-less and flair-less, making him all the more terrible. Madame Simza was great, Watson was perfect, Robert Downey Jr. mastered Holmes wonderfully.... And the film gave you the tools to figure it out, if only you were as insanely brilliant as Holmes. Which, of course, we are not, but it is more satisfying at the end. I definitely recommend watching it, and I think I'm going to go see it again.