Take a look at open web apps / chrome apps / phonegap / the Firefox OS project (I work on the latter). The line between apps and websites is getting thinner by the day, and getting very close to being non existent. Also the 'apps are an island' comment is quite specific to iOS, Android has a very elegant system for allowing apps to interact with each other, one which the web is adopting (web intents/activities). The…
I only know a little bit about the Firefox OS project, but if you give control to the OEMs, won't you run into the same problem that Android has with fragmentation?
On one hand, I don't want to be naive. Everything on the desktop has moved into the browser. That happened a lot faster than I though. Everything in mobile is moving 2x the speed of desktop, so will everything move onto a browser in mobile eventually too? The key difference between the desktop and mobile is that there isn't hardware ubiquity. Every computer has a keyboard and a mouse. But the hardware buttons aren't standardized across Apple and Android. The home button is crucial on the iPhone and same with Android. Would either of those platforms ever cede control over that button to a browser? Otherwise, you've got to put that functionality on the screen which takes up space.