I just saw Sherlock Holmes yesterday with my sister. I absolutely loved it!
Robert Downey Jr. and Jude Law (whom I'm normally not a huge fan of) played the pair of Holmes and Watson perfectly. Everything was fantastic, from the late 19th century London set (complete with partially constructed Tower Bridge), the costumes, and the score.
Rachel McAdams was fantastic as well, it was nice to see her as a criminal vs. her usual roles. I think the best part was psyching me up for my London trip. I hope they continue with this series!