Nice Work!

I have been working a lot with JSONP lately it's a great way to bring content Cross domain/into Apps. I just recently finished writing a Webservice/iPhone implementation.

Something to consider, try preloading the content to give the user a smoother experience. My UITableViews (iPhone) were a bit clunky until I got around to pre-caching my JSON results.

Anyway, Keep up the good work!