I think the problem might be that Phonegap allows people to develop rich internet applications. From there, it's only a hop and a skip to implementing a web browser, which they do not want app developers to do. Look at these two pages to see how I arrived at that theory:
http://groups.google.com/group/mozilla.dev.platforms.mobile/...
http://gizmodo.com/5072333/opera-for-iphone-ready-to-go-if-n...