I'm guessing you're the Quasar guy or am I off? Either way, I think you have benchmarked the lightweight thread approaches on JVM's. How much simultaneous concurrency can the JVM methods manage right now for say serving web requests? And how much does Erlang's best do on same machine?

I think that's an interesting and useful comparison point to start with to test your claim. This is also something I figured Java side would greatly improve on.