...I kind of agree with Keith Vaz
Okay, so there's not much actual onscreen violence, but the repeated threats are pretty intense, and it's basically one huge downer from beginning to end. I wouldn't feel comfortable taking an 11-year-old to see it.
I can understand why they 12A-d it, though, if it was 15 the ushers'd be trying to hold back an oncoming flood of underage kids determined to get in.
(I seem to recall that the original 12 certificate was invented for the first Burton film, incidentally.)