This version of Sherlock is set in modern times. To me that is the biggest reason for you watch this show in the first place... I can't imagine any other character fitting into our world so beautifully.
Benedict Cumberbatch plays Sherlock like he was Sherlock in a previous birth. Martin Freeman plays Watson and is the perfect foil for the mad, charismatic Sherlock.
And yes, Cumberbatch grows on you... that you can't imagine anyone else ever playing this character. And after i think 2 episodes i began to realize that the man is smokin' hot!
Watch Sherlock... it's a very intelligent and interesting show.