I think 'race' is one way of looking at it. Another way to look at it is that there will be more than one 'winner'. Just like today, I think in the world of tomorrow people will use more than one programming language. So all of the languages that expect to be around tomorrow will need to evolve into languages for controlling concurrent systems on massively parallel architectures.
You are correct in saying that some languages are simply given as winners.
Erlang is a VERY impressive language from a performance standpoint. That said, it really needs to be used in conjunction with some front end UI language to present the results of all of its processing. Make no mistake about it, if one has so much data that one will need say 32 cores to process it, then a clever presentation layer is a must. Another drawback here is that, for those Erlang programmers who are something other than elite, Erlang will handle all of the locking and synchronization on its own. I think experienced senior programmers see where that one is going. That said, the way Erlang implements concurrency is cool. I like simple!
In my opinion, Java is another clear winner here. From Wall Street systems with US$900,000,000,000 a day in transactions flying through them, to medical imaging systems rooting out cancerous pathologies, to petroleum exploration systems trying to find the precise limits to all of that new Cuban oil, Java is at the center. When it comes to handling massive datasets in a maintainable fashion, Java is second only to the C,C++ languages. Some would even say that C or C++ code is less maintainable than Java. I would say they should hire new C programmers.
Lastly, C, C++ and Assembly will always be around because there will always be someone,(Carmack) who wants to outshine everyone else. And we can all agree that nothing flies like an assembly routine. As a bonus, we can get exacting control over concurrency, synchronization and locking. It may be difficult to believe, but this option is attractive to a certain class of hacker.
Concurrency in todays web darlings, Ruby, PHP, and Python will be challenging. I think someone out there will simply come up with a new language. Or the web guys will switch to Erlang over time. They will run into a data size problem though due to the way Erlang implements concurrency at a low level. It will be interesting to watch them problem solve that.
On the front end, it's easy . . . Microsoft wins. Anyone who understands concurrency in an intimate fashion knows the challenges of getting a scripting language like JavaScript to support it in a satisfactory fashion. Do you lock and synchronize for the developer? Do you let him/her? Do you copy the heap and send messages? What about client side memory in a tabbed browser? The questions go on and on. Java may have somewhat of a chance here, depending how things go, but basically Microsoft will continue to have the majority lock.