Yeah, this is a big deal. It enables very interesting opportunities to create a map reduce engine that isn't awful or which requires Java.

People use Hadoop because they have to, not because it is great. Isn't it time for a better alternative now that the toothpaste is out of the tube re: map/reduce?

Java doesn't even have hash literal syntax! Why would you ever want to query document oriented data with it as your language of expression?