Regarding speed, my thoughts exactly. I'm a Ruby programmer and I see this being thrown as a weak point of Python/Ruby all the time. I remember the days where Javascript and PHP were supposed to be slow. Now that Facebook/Google/Apple/Mozilla have thrown dozens of millions of dollars in across the board optimizations, they aren't so slow anymore. Not C-fast mind you, but (especially for Javascript), definitely not languages you can call slow anymore.

It's really only a problem of investing enough money for JIT and GC technology that would make any language "fast enough" really.