I loved it. It kept me guessing pretty much all the way through and I didn't seem much of it coming at all. Er, despite the clues. I have no real complaint about Tesla's invention - it allowed Jackman's character to "get his hands dirty". Plus, I'm really happy to go with my imagination. It's not like the film was grounded in reality (okay, it was set in Victorian times, but it was hardly a period piece).
Christian Bale was outstanding (again). When I first heard him speak in his bizarre Cockney accent, I was wondering how he'd pull it off. I wondered exactly the same thing when I heard him speaking white-boy gangsta in 'Harsh Times'. But there was no need for me to worry. His combination of subtlety and intensity wins me over every time. I seem to have sympathy for him even when he's playing complete prats (like Patrick Bateman).
Oh, and Michael Caine was masterful again. He seems to have received a new lease of life in the last 5 years.