I just ordered it from Zavvi this morning for £76.46
(with a mystery discount code they sent me). They haven't shipped it yet though, so if it's much cheaper at Amazon I think I'll buy it (if it doesn't sell out instantly) and cancel from Zavvi o.O.
I get the feeling it's going to be one of those releases that drops dramatically fast in price, but I just can't hold off any longer, it's such a long time since I've seen some of these movies.