We don't necessarily need new language features, we simply need bright people to sit down and think about the right way to express parallelism in Python and then write libraries (maybe in the stdlib) that implement those ideas. <KS> Exactly. This PEP is about this thinking about expressing parallelism in py.
While I too love to think about parallelism, until the limitations of the GIL in CPython are fixed, all our grand thoughts will be dead ends at some level.
Also GIL is a challenge only in one implementation (I know, it is an important implementation!) My assumption is that the GIL restriction will be removed one way or another, soon. (same reason, quoting Joe Lewis)
I am not that optimistic I guess. Hopeful though.
What we need to do is not to line them (i.e. GIL removal, parallelism) serially, but work on them simultaneously; that way they will leverage each other. Also, what ever paradigm(s) we zero-in on, can be implemented in other implementations, anyway.
If there were infinitely many people willing for work on this stuff, then I agree, but I don't see even a dozen people hacking on the GIL. And in my mind, once the limitations of the GIL are relaxed, the other parallel stuff won't be very difficult given the work that people have already done in this area.
Moreover, IMHO, we need not force the GIL issue just yet. I firmly believe that it will find a solution in it's own time frame ...