The charts are for general language use, not specifically concurrency. Go and Clojure are better than locks and mutexes of C, but there were similar ideas in Scala and other languages along the way and the newcomer improvements don't land far from those.

So Go, Clojure, F#, Scala, Python could proabably be lumped into the same ease of implementation category as far as concurrency. They'll all make a mess if you have complex control flow. This http://news.ycombinator.com/item?id=1824683 (which you've already seen) or http://en.wikibooks.org/wiki/F_Sharp_Programming/Async_Workf... is what I call a mess, but it's as clean as it gets for now.

I think the real test is whether people start using concurrency as the norm and not as a separate use case (since it's annoying to write). I don't think these languages will have that effect.