in the meantime, my android browser doesn't seem to be caching websites aggressively enough, because it seems to take up to several seconds to load the (few) bookmarks i have. so native content-oriented apps are faster, for now.
Accelerometer, native graphics, etc are the key features I think about that are not well suited for web apps.
My startup, AppStoreHQ (http://www.appstorehq.com), is a huge believer of mobile web apps, and we even have a private alpha going on for monetizing your mobile web app (check out an example like fortysquires: http://fortysquires.com ).
http://github.com/raganwald/iGesture
After drawing some naughts and crosses, you can rotate the board by placing two fingers on the screen and rotating them 45 degrees or more.
It's all Javascript and jQuery.
Thinking even more generally, what makes a mobile device so different than a PC? Why would the evolution we've seen on PCs play out any differently on handsets?