rust, I hope you never get into the voice over business because you really don't have a clue about it.
What defines the best person for the role? Can anyone really define that? The director will have their preferences. I really don't believe for a second those actors were chosen soley because Disney wanted to shoe-horn them in. The difference between a pro voice actor and a pro stage or live action film actor is minimal in the business. Of course the difference is you act soley with your voice which has it's own challenges as does stage acting and such but here's the thing at the core of both is acting and only acting.
You seem to be confusing voice acting with character acting. Character acting is one kind of acting but so is emotion acting. People who do emotion acting do one voice primarily and they can do a lot with it and even in voice acting circles there are people who only do one voice and it's not because they aren't good it's because they never developed a wider range. Those people do quite well for themselves considering they usually get lead roles (yes I'm talking about Lowenthal and Bosch here but both of them can at least do variations of their norm).
Character actors are just that. They take on a nuraber of characters and can do unique voices for each and perhaps even sound so different you don't think it's the same person. They're not neccessarily more skilled or more proffesional than an emotion actor but they have a lot more they can offer a project in which you try to get the most out of each actor. But then they rarely get a lead role so it's a bit of a double edged sword but guys like Scott McNeil manage to get some unique lead roles (Wolverine for instance) because the lead calls for a unique voice.
Now getting back to Ponyo. I'm sure the dub will be great because none of those dubs have been mediocre and if you don't want to support the movie because you feel it supports Disney shoe-horning their marketing into movies that's your call but I think it's a really petty complaint because I really don't believe they just handed those roles over to the actors they had to audition and they got picked because they were good actors not because they could be good marketing. Even in the case of shoe-horned celebs parties like Dreamworks films people don't get casted merely by their names and people don't get famous without having some level of talent.
What I dissagree with you most of all is the belief that a famous or established actor isn't as well suited for an animation voice over as someone who already does animation voice overs because it's all acting and they probably would do more voice overs if they didn't pay so lowsy. Pro film actors enjoy voice acting because it's a lot more flexible than stage or film acting. They didn't get to be famous without the talent neccessariy to get there. Sure there's probably someone who would be better but you know what? I bet that person hasn't even been discovered yet and wasn't around to audition for the roles in question. That's just kinda how it goes because there is no "perfect" choice when it comes to voice acting and it mostly comes down to the preference of the director.
I honestly don't care if you don't go see Ponyo's dub because of some self-righteous belief that doing so makes you a tool of Disney's marketing machine I just think your argument is silly and immature. You can be stubborn but I expect you'll end up missing out on a great dub. The Miyazaki film dubs are always superb and some of the best in the business. I don't see that changing especially since they've always thrown celebreties into the mix and I enjoy hearing those actors in roles they would not normally play. It shows much versatility on their part as actors and I greatly respect that. If you don't want to see it, it's your loss and no one else's.
