AltRaps get my vote.
His work in Roll Call is insightful and very funny. Often it's the only thing that brightens up my day in my otherwise boring life.
Arsenalist is a close second. His columns are informative and generally interesting to read. I can't imagine the time he spends working on those "Breaking it Down" pieces. For someone like me, an average fan, it really gives basketball a new dimension and makes the game even more enjoyable than it already is.