Miyazaki was nominated for an Oscar for the 2005 release of Howl's Moving Castle, after winning one for 2002's Spirited Away (He also directed Princess Mononoke). I was at the Disney panel at the Sand Diego Comiccon when he received a standing ovation both when he entered the room and again when a clip of this film was shown (he also received an Inkwell Award from the Con). I watched as fans in anime costumes gushed and fumbled like the tweens in the Twilight panel. In short, the man is an anime legend. For the United States release of Ponyo, he has brought some A-list help.
First, like his other works, the film is distributed by Disney. (John Lasseter has admitted to being a longtime Miyazaki admirer). Second, Melissa Mathison, the screenwriter behind E.T., the Extra-Terrestrial, wrote the film's English-language adaptation. Third, and finally, the film has attracted A-list voice talent (Liam Neeson, Tina Fey, Cate Blanchett, Betty White, Lily Thomlin and Matt Damon.) Also look for Noah Lindsey Cyrus (Miley's sis) and Frankie Jonas (little brother to the Jonas Brother), who do an excellent job voicing the lead characters and, of course, sing the catchy title song--it is a Disney movie after all.).
But, the real reason to see this film is for the incredible visuals. The film features traditional hand drawn cell animation. I don't know for sure, but I would guess that film uses water colors (like 101 Dalmations and Lilo and Stitch) to create the pastels in the animated world. The psychedelic imagery of the water as a living creature is fascinating. Every scene highlights amazing creatures. And while they are not necessary for the story; the presence of these fantastic mythical beasts show the amazing world that Ponyo inhabits without beyond as over-the-top as Miyazaki's other anime.
As a final note, I saw this with my four year old daughter, Elizabeth. She absolutely loved the movie. As you can guess, the overarching themes of ecology and balance were completely lost on her. That being said, all she really needed to know to enjoy this film was that, "Ponyo wants to be with that little boy and he likes her too." I was a little disturbed that Lisa, Sosuke's mother, would leave a pair of five year olds home alone during a natural disaster. But, perhaps my view would be different if I knew one of those kids was a magically transformed goldfish.
I recommend the film (definitely if you have kids). It is also the most mainstream of Miyazaki's work.