As long as it costs money and is not open source, this will never become hip amongst the cool guys.
IDEA costs money, is not fully open source but is still hip. What gives?
The problem with frameworks like Play, or Symfony in PHP world is that they only play catchup to frameworks like ROR and Django and since they started way later, they still lack the polish.
Or alternatively, they learn from the problems of older frameworks, and can bring a fresh approach without having to worry so much about backward compatibility.
Why is this a problem? They will tend to choose to implement only the best practices. For example my (I'll admit biased) experience with play framework was better than with RoR and with Django.
It would be nice if this framework get more traction