I like the approaches of both webOS and Firefox Mobile OS. For sure Javascript might not be the language one would choose to start with if one was re envisioning the web today with all the last decades learnings. And perhaps a fresh start could see lots of the incidental and accidental complexity dropped from CSS and HTML. But they are what we have today, and perhaps in time Javascript can align itself more closely to Scheme and a WebCPU element can come along to allow near native code where needed.
I have difficulty seeing a strategy underlying Google's effort with Java/Android - I dont see where it fits for a web company. The App / App Store centric distribution model is a step away from open exchange of information, and the whole App updating model seems very pre- web. Building up yet another Java ecosystem for UI seems another miss step like the original MIDP/J2ME disaster - what is it with Java encouraging non domain experts to implement libraries and frameworks?. Particularly as the web seems to move farther each day from Java in the browser.
Also iOS is quite uninteresting to me from an application development perspective. It has a very 80's feel to it with hard coded apps encouraging fragile pixel precise layouts. It seems primarily about building a money pump around a closed eco system. Some elements of the system are beautiful executed - the whole CoreAnimation / CALayer giving fluid graphics composition for example. But for the vast majority of throwaway apps the level of effort needed to implement native Apps - which for the most part are a gluing together of OS APIs seems like overkill.