Poo-poo on you naysayers, this is a very enjoyable film. It has action and suspense and Downey and Law did a great job portraying Holmes and Watson.
I did a lot of reading before I went to see the film and they did lift a lot things from the Conan Doyle stories that were mentioned (such as Holmes being a expert pugilist and his knowledge of martial arts) but never actually shown.
This story is an original one, but it looks like Warner Brothers have hope for a franchise. Moriarity does make a couple of appearances (sort of).
Another thing I would mention is that the rumor that Holmes and Watson are portrayed as gay is total BS.
*** out of ****. The plot got a bit messy in the 2nd half but the acting/casting was perfect.