There's a bit of controversy on whether the US dubbed soundtrack will appear on the Japanese Region-2 Ponyo Blu-Ray this December. GhibliWiki says no, while AsianBluRayGuide says yes. Unfortunately, no official press releases are available to read, so we're left with guesses and reading tea leaves.
For most of us, this is a moot point. Ponyo on BD should be released in the US this December, and both the US and Japanese soundtracks will be included. We will do perfectly fine no matter what happens. But I would still be very surprised to see the R2 Ponyo so stripped-down. Multiple languages are typically standard on Ghibli's DVDs; the Mononoke 3-DVD set included eight soundtracks on the second disc, including the Miramax dub.
It's an interesting topic for discussion, but pretty minor stuff, really. We'll just get the American Blu-Ray for Hannukah.