I don't understand the hatred of Java and love of JS. Is Java not open source? And isn't Android open source as well? Note that Google apps are not part of the core of Android.
I don't hate Java, but I hate to write the same application over and over again, one for every platform out there:
- the desktop web
- the mobile web
- iOS
- Android
- Windows Phone
- ...
With JS there is a little hope that we well be able someday to write the app once, and make it work on every device out there, if it is from Apple, Google, Microsoft, Samsung or whoever wants to enter the market next.
We are almost there, but we need hacks like PhoneGap/appMobi to make it work, and it's not optimal at the moment.