A bit late for this, but I just saw it and boy was it good. This is one of my favorite movies now.
They really nailed the suspense and you could feel the pain of the drummer.
EDIT: Also I loved J.K Simmons' creative use of profanity to insult the band members.
EDIT_2: Also loved the song "Caravan" and the time signature in "Whiplash" was good (14/8 if you're interested).