I think your getting very worked up over nothing....pretty sure they guys here are just joking around...
I thought of WoW as well, having farmed that bastard for years (and still haven't had the helmet drop!). There is no problem not knowing about an predominantly american culture reference if you aren't from the states. Big deal. I knew the story before so realised where it was from, if that was your first exposure to the legend then you probably would think it was originally from WoW.
Just don't be like the guy that was ranting how lord of the rings ripped of WoW with orcs, goblins and wizards lol.
Anyway, I saw the pilot last night, I really think this would have made a better TV movie. I was ok but will they really be able to spin an interesting story over 12 - 22 episodes and possibly multiple seasons? Its really going to have to deviate (even more) from the original premise and if so, why call it sleepy hollow in the first place?
I'll give it a few more episodes