I found some time to watch this since nearly everybody I know has been raving about it. Overall, I enjoyed it much more than the film adaptations. Compared to the films, Sherlock managed to IMO capture the essence of the characters (well, most of them) and story more faithfully despite the contemporary setting. And I love the visual flair of the series, particularly the way they depict Sherlock's thoughts and deduction process. There's even a very Minority Report-like scene where Sherlock goes into his "mind palace" and sieves through his knowledge looking for the pieces of relevant information. It's a little over-the-top but I really like it.

The casting for Sherlock and Watson is brilliant. I could never remember Benedict Cumberbatch's name (not so anymore) but could recognize him due to a couple of strong performances. I first noticed him in Amazing Grace where he played William Pitt and practically stole all of his scenes. Then I was impressed with his slimy turn in Atonement (but James McAvoy stole that film). His portrayal of Sherlock Holmes is fantastic. The borderline arrogance, impulsiveness, chaotic habits neatly combined with the logic machine that he is and the few moments when his humanity slips through. Martin Freeman is equally excellent as Watson and brings a lot of pathos in his performance, especially towards the end of the second season. The two actors have remarkable chemistry and really infuse the friendship with a lot of humor and emotion. Their relationship is the main highlight of this series.

( MAJOR SPOILERS behind the cut )