I'm really rooting for Phonegap. I really want to write apps written in html5/css/javascript, but what is really need is "proof" that it is possible to write a great app using these tools.
I've seen all the demos, and all the Phonegap apps in the App Store, but none of them are "killer apps". They don't have many ratings, and the ones that do have several ratings aren't so good. Hoping this changes soon.