Well there's also PhoneGap (Apache Cordova), jQuery we contribute too and as well as Webkit now. On the enterprise side CQ/Day is built off Apache Jackrabbit which Adobe engineers contribute.
well I'd look at the community building around PhoneGap Plugins for your answer there. I do agree that many of the standard APIs (which we lead/follow W3C on) will be in most mobile browsers in the coming years.
there are a number of Android apps built with PhoneGap. Admittedly the Android code is not as polished as the iPhone project at this point. But we're working on it!