Reason #1 is the most obvious: Sherlock Holmes is played flawlessly by Benedict Cumberbatch.
AKA AN ACTUAL GOD AMONG MEN.
Plus, he just won an Emmy for his performance as the famous "consulting detective."
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Martin Freeman's portryal of John Watson is equally perfect.
His Watson compliments Cumberbatch's Sherlock wonderfully. So much so, that he too just won an Emmy for his performance in the Series 3 finale. He keeps Sherlock in check, respects him, and also has skills of his own to bring to the table.
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It is set in modern times.
One of the innovative things about creators Steven Moffat and Mark Gatiss' version of Sherlock is that it is set in present-day London as opposed to the Victorian period. (And yes, this came out before CBS' Elementary.)
Sherlock with a cell phone? Genius.
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It's actually very funny.
Sherlock is a total asshole to everyone because of how superior his intellect it, and everyone else makes fun of him for being so awkward. Hilarity ensues.
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