Sounds like they're essentially advocating an Erlang-style model of concurrency, which generally seems to be recognized as a good way of doing things. That sai

Sounds like they're essentially advocating an Erlang-style model of concurrency, which generally seems to be recognized as a good way of doing things. That said, they're not really eliminating all the pitfalls of threaded programming. It's still possible to have deadlocks and timing-dependent bugs when using a message-passing model of concurrency. To take it one step further, they could implement something like the Erlang OTP behaviors to abstract out the concurrency primitives. (Not that this would totally eliminate the drawbacks I mentioned, but it's another incremental step above the approach they've presented, IMHO.)