In the long run, Ruby implementations will be at least 1 order of magnitude faster than either MRI 1.9 or JRuby. And I'm glad to see that the Rubinius folks are taking the necessary steps to get there.
I don't remember how Vyper worked, but it might have abolished the GIL too: http://got.net/~landauer/sw/vyper_readme.html
0: https://github.com/rubyspec/rubyspec 1: http://rvm.beginrescueend.com/
My understanding is that the rubyspec project (http://rubyspec.org/), is an effort to retrospectively document all the stuff the language does.
Compare ruby: http://eigenclass.org/hiki.rb?Changes+in+Ruby+1.9, to python: http://docs.python.org/dev/whatsnew/2.7.html
I appreciate this isn't a great example, as python 2.7 isn't a different implementation (ruby 1.8 -> 1.9 is though), but this has been my experience of the way things are documented language-wise.
Having "lots of exciting choices" in your web server, your database, your object server, your language implementation, or monitor size just says your time will be sucked from real work.
<almost a flame> I have been tempted, in the past, to wildly claim that if you compare Rubinius' relative failure compared to PyPy, Rubinius is kind of a poster-child of Test Driven Development's failure. IE, languages need semi-formal specs, not tests that claims they are a standard (no amount of testing can prove two implementation equivalent). </almost a flame>
<CAVEAT>But listening to the PyPy folks describe their process, I realize this stuff is uber-hard and I'd just like to hear what a real compiler developer would say about this. </CAVEAT>
I've done more Ruby than Python altogether. It's true that I am no longer doing Ruby - mostly because it is too slow for anything beyond a fairly simple web platform (I would welcome an improvement in Ruby performance).
I would argue that the time spent on the tests could instead be spent on an actual spec.
The thing is; C# and Java are also fast enough for an adequate desktop GUI. But they're horrible to program in.
Ruby and Python are still in about the same category of slowness even with pypy's success. I'm doubtful of Python desktop apps but I know they are out-there.