I was really hoping that Bale's character would turn out to be a "wizard." I mean, they already had the sci-fi/fantasy element with the cloning machine, so why not have someone actually be able to perform real magic?

Is Bale's twin actually a twin brother or was he cloned by Tesla?

David Fuckin' Bowie as Tesla!!!!!

I'm thinking that Borden was so poor starting off cause he saved up all his cash to get Tesla to make him a clone. I'm assuming it based off a few things, but primarily when he talks to Angier's double about doubles having control. In Borden's case, his double is actually him, so he doesn't have to worry as much about betrayal as they're the same person, united in the same goal. That's also where Angier's character has turned evil in that he kills all his clones.

How could Bale have a clone? Tesla had no idea what the machine was doing until Jackman's character stumbled upon the hats and cats and that came long after Bale started his transfered man trick. It was his twin.

I don't think that Bale would've had the emotional attachment he does towards the other him if it was just a clone.

Then why was the secret key word to Borden's diary TESLA? That, combined with the speech about the double hinted at the idea that Borden had a clone. The difference was that he was more human in that he cared about the well being of his clone unlike Angier. His emotional attachment was what made him the hero and ultimately the better magician. The process that Tesla performed for Borden could've been different. Tesla seemed to know exactly what Angier was looking for when he approached him. He might've just had some kinks to work out with building a new machine. Remember he said that "exact science is not really exact" or something to that effect. He was creating an electric cloning machine at the end of the 19th century!!! You'd expect it to have some unpredictable results as well as moral conflict.

Well, what I got from it was that he made his keyword Tesla because the notebook was a setup and he was deliberately sending him halfway around the world on a wild goose chase. After he came to the end of the writings and discovered it was a trick, he confronted the assistant and they had a back and forth to the effect, "You lead me to believe you built a machine for him," to which the assistant responded that they never said exactly that.

It's in no way definitely said either way, but thinking back, the whole movie gears clues towards Bale's character being two people as early as before the drowning accident of Jackman's wife.

It's pretty obvious it's a brother. Hence the ability Borden had to see the old Chinese guy's "trick" so easily while Angier had trouble. He LIVED the lie, just like the old man did. It was the greatest illusion they could do. The diaries they pretty much ended up exchanging were pretty much purposefully done to fuck with one another. Hence addressing the reader personally at the end, like a "Gotcha, bitch!"

Or he might just have been inspired by the old Chinese guy to make a double for himself, and live as the same person. Also, why would he send Angier halfway around the world to Tesla, only to find out that he acutally had a way to create doubles for himself? The key to his notebook could've just as easily been Lima, and he could've sent him to Peru or some other random ass place to find nothing and throw him off. I don't think that sending him to Tesla (and the fact that Tesla didn't even have to ask specifically why he was there) and then Tesla happening to actually be able to create a cloning machine was a lucky coincidence. The only clue that blatently references the idea that it was his brother was when Borden does the trick where he makes the bird disappear and the little kid starts crying. He makes a bird re-appear, but the kid still cries, "but where's his brother?"

But what about when Angier was given a demostration for Tesla's machine, and they had no idea what had happened. More misdirection or did they not know how the machine was behaving?

Also, did anyone notice how in the advertisements for the Prestige they presented Bale's character as the bad guy, while Jackman's was the good guy? This movie was set up on misdirection from the beginning.

The previews made it seem, at least to me, that it was Bale's character who was suggested was performing "real magic" when in the end all he had was a very well-protected trick. I definitely agree the movie was all about misdirection even as far as the previews, and I thought that that was a really cool part of it.

From what I gathered, Telsa and his accomplice knew what the machine would do, at least roughly, which was to create duplicates. I thought that they were expecting the duplicate to appear close by; and this was why they said that it was not an exact science, when they found out the duplicates were way outside. Just because they didn't know why the machine wasn't behaving the way they expected doesn't mean that they had never built the machine before.
It seems apparent, from when Jackman's character approaches Tesla, that Tesla knew exactly what machine was being talked about, and exactly what it was it was intended to do. It doesn't seem like coincidence at all.
With that in mind, I don't think it was obvious at all that Bale's character had a twin brother, as Jessykins said.

Also, for the person who talked about Angier having a lack of compassion for his clones, or whatever, I don't think that really was the case. I think he fully viewed it as killing himself, not other clones, which he wouldn't have to care about. But of course, he didn't mind either, since Cain's character had told him that the sailor felt "like he was going home" when he was drowning; and in addition, he was consumed with his anger and spite towards Bale's character.

What about when Tesla's assistant made a comment after they discovered all those duplicated hats in the surrounding area, stating that they didn't bother to check the hat since it didn't move. That led me to believe that Tesla knew Angier wanted a teleportation device, but it turned out to be a duplication machine. After all it's not an exact science.

Yeah, that's true. I think I was basing that assumption off of Borden's statement of something to the effect of "You did terrible things" in reference to killing the clones. But yeah, I can see where you're coming from. Also, he might have been drowning them as a twisted means of self torture since that was how his wife died.

Also remember that there's a certain amount of ambiguity about whether or not the clone was the one transferred or if he was the one that remained in place. By the end of the movie, Jackman's character was most likely already a copy of a copy of a copy, the original long since dead.