The debate over dubbed anime versus English subtitles has roared through many years, as fans often cite that they are concerned that bad translation, or perhaps translation that tries too hard, overwrites the original storytelling created by the Japanese artists. The new release of Ponyo will be interesting as there will be no special transliteration done to the voices, but voice actors will be watching the video, also trying to match the lip movements, and recording several times to see what works.
Interestingly, Tina Fey plays Ponyo's 'very modern mother'.