I think it's a bit unfair to make a judgement on the dub simply by watching the trailer, which will no doubt have been put together, complete with syrupy music and titles, to attract American audiences. U.S. film critics have given Ponyo glowing reviews - Dana Stevens at Slate was going to simply write "Just watch it" as hers - so they must have captured something of the intent of the original. I must admit my heart sank when I read the Cyrus and Jonas names too, but as you say if it attracts a wider audience then so much the better.
The worst dubbing experience I ever had at the cinema was Jeunet's The City of Lost Children, which was released in both an English dub and in the original French. I somehow managed to watch the former instead of the latter. As I recall, the English actors played it in a very Pythonesque style, which completely detracted from the darkness of the film.

People have compared this to Goodfellas, which I think is pretty generous. It reminded me more of Stander, the South African film from 2003 starring Thomas Jane, which is remarkably similar in its narrative and themes. Neither are bad films exactly, but I don't think they will be troubling the pantheon of classic gangster films too much.
(Made me split my comment again - I'm writing these too long?)

Just saw Killer Instinct last night. Good review - summed up a lot of what I felt after watching it. I was frankly a bit disappointed. Richet spends a lot longer focusing on the violence and audacity of Mesrine's raids than the motivation behind them. It seems to take his charm and notoriety for granted almost, spending much more time detailing his love affairs and heists than his wit and eloquence - if that is what he had. I didn't think it was well plotted either. If you're going to make it a two-film story arc, then give us something to come back for. Richet sets up a mystery of sorts in that we don't know who killed Mesrine or who shot Guido in his club, but fails to make more of those scenes, or focus on the men trying to stop the criminals enough that we'll give a damn. Instead it's routinely episodic. Mesrine kills someone. Mesrine bangs hottie. Mesrine robs someone. Mesrine goes to jail. Mesrine breaks out. Mesrine kills someone. Repeat.

None of this will stop people like CLF sounding off on whatever academic theory strikes them as being Von Trier’s main thesis. To them I would say this: the man’s not an academic, he’s a showman. Why else do you think his films go on widespread release? He’s like every other mainstream director in that he makes films to elicit emotions from his audience, whether it’s laughter, shock or gasps of fear. There weren’t enough of any of these in Antichrist, in my opinion.

(sorry, server made me split my comment into three parts!)

Having said that, I’m not sure that the film deserves academic scrutiny. I think Von Trier has picked up bits and pieces of gender theory, written down some of his negative experiences in therapy and muddled it together with some horror film tropes. I struggled to find anything coherent about it, and you have to suspect some of the pyschosexual horror setpieces of the last 20 minutes were put in simply to shock the audience into a reaction. Would we really be talking so much about this film if it wasn’t for those scenes?

Despite CLF’s rather overblown style, he/she makes one good point about critics who have dismissed Antichrist as a practical joke. It’s not only Bradshaw but Kermode too, and Andrew O’Hagan in the Standard. It does seem like a bit of a cop-out, but I think this would be a very difficult film to critique for the general public. Simply saying Von Trier has created something no more meaningful than a joke avoids a complex academic reading of the film which might be unpalatable to a mainstream audience.