This is great news, especially coming from some one as superb as Michael Caine, I mean he had a TV show about how to be a better actor, and he is the man, if some one made him forget his lines, thats awesome.
And Tempest I completely disagree with your statements and a lot of people's statements on Mark Hamil's Joker. To me he's first and foremost created for kids for the most part, and just because he giggles a lot does not make some one a psycho. I mean with a cartoon you can't get the human feel for something, that feeling you get when you see some one's eyes or expressions.
That and Hamil's Joker is just too eccentric, to "funny" though he does terrible things in the TAS which I have seen all of them, it's just he's not that scary. Just because he laughs creepy does not mean he's the ultimate Joker. So I just hate when people pull comparisions to Mark's Joker and Heaths. Hamil will never be able to achieve a great character like Heath has the chance to.
Being not a cartoon, Heath can pull people into the movie with real substance, and real human expression, and I have a feeling this will be the best interpertation of a truly demented anti-Christ of a Joker we have ever seen.