Not much, really, the benefits of intrinsic support for concurrency in languages are very overhyped.
Java is a great illustration: it has syntactically close to no support for concurrency (synchronized, pretty much) but it has been able to keep up with today's concurrency challenges by the simple virtue of its libraries (java.util.concurrent is very, very powerful) and ingenuity of its developers.
The amount of concurrent Java that powers major web sites and other places that we don't even know of is simply staggering.
Java is a great illustration: it has syntactically close to no support for concurrency (synchronized, pretty much) but it has been able to keep up with today's concurrency challenges by the simple virtue of its libraries (java.util.concurrent is very, very powerful) and ingenuity of its developers.
The amount of concurrent Java that powers major web sites and other places that we don't even know of is simply staggering.