Although, Ruby doesn't have any iteration constructs as nice as Python's generators. (You could create them using call/cc, but I expect the performance would be awful).
Scala code compiles to Java bytecode, and performs comparably to Java code. It's just as portable and performant as Java, which means very portable and fairly performant.
I like lua and am using it for some tasks where I'd have used C in the past. But for many things where ruby/python have strong, pluggable libraries (e.g. everything web-related) there is simply no equivalent in lua-land.
Kepler project is nowhere near a django or rails.
FWIW, I'm working on a lightweight, event-driven webserver and general server framework (like twisted or tornado). It will be released under a BSD-style license at the same time as my distributed filesystem (the project driving its development).
Yeah, absolutely not true. You need to do a little more research before you say very silly things like this.
Compared to older scripting languages (Perl), Python offers a sane language and a rich programming environment.
Compared to other current popular scripting languages (Ruby), Python offers a solid runtime and better out-of-the-box performance at the expense of some elegance and fluency.
Comprare to some very interesting languages (Haskell, Erlang, Scala) Python is more widely available and allows you to produce good, portable, well-performing code quickly and easily.
It's a state of flux. Right now Python is my language of choice (after ten years of Ruby) and it touches that sweet spot of expressiveness and performance. However, the bolted-on features (verbose object system, clumsy metaprogramming) deliberate crippling of language (e.g. one line lambdas) and the underlying message of "there's one way to do it" (which is my way, because I know better than you) will, for me, mean that eventually I will move on. More expressive, coherent and flexible languages will eventually reach Python's current level of maturity and performance, and then it will be time to switch. It could be MacRuby, Scala or F# (but probably not Haskell or Erlang). Who knows.
But, for now, Python is a good choice.
Edit: typos.