I was hoping that Python threads split across processors, but it seems that they don't. Is there a language that does it "automagically" without having to explicitly code it?
Another pretty exciting language you might to look at is F# - presently running under Mono on my macbook.
Finally, if you love your python (who doesn't? ;)) - see http://www.parallelpython.com/ for some interesting work.
From my experience average increase in speed gained from porting to C/C++ (even without using multi processors) is about x60-x100.
Understanding concurrency in Python: They're called process-ors, not thread-ors... ;-)