I've never seen a Miyazaki movie I didn't enjoy, and Ponyo is as charming as his other work.
On the animation side... is it just me, or was the animation very uneven? For example, in Fujimoto's underwater dome, the second time we see it people have air bubbles coming out of their mouths, but the first time they didn't, so I was initially confused if it was full of air or water. It just seemed that the animation was more detailed in some scenes (like the rain storm) than in others (like every scene before the rain storm). Joy felt the more simplistic animation in some parts of the film was intentional. I know Miyazaki is famous for "every blade of grass moves" in his animation, so were my expectations too high?
Overall I have to say I wasn't wowed, but I enjoyed the film itself. Miyazaki never disappoints. Ponyo and Sosuke are both charming characters, and it's great to see their devotion to each other.
Plus I think it's great that I live in an age where I can rent the latest Miyazaki movie from a mass-produced mainstream Redbox for a buck and have it be a faithful, uneditd, high-quality dub. (Or I could have even watched the sub! But we were renting it for Mylene, who prefers dubs.)