I agree with most of your points but the major difference here with Play are 2 points 1. This framework is geared to asynchronous/real-time workloads (think no

I agree with most of your points but the major difference here with Play are 2 points 1. This framework is geared to asynchronous/real-time workloads (think node.js) 2. The framework is built for Scala, which they state is a more productive language for the JVM "Code sizes are typically reduced by a factor of two to three when compared to an equivalent Java application." Note: I admittedly don't know much about Ruby so I'm not sure how much it would or would not compare.