[carbon8]

Then you are testing two different things, and if you use tail recursion even Ruby 1.9 still runs it faster than Python.

  # 400
  $ time ruby fib.rb

  real	0m0.017s
  user	0m0.010s
  sys	0m0.006s
  
  # 400
  $ time python fib.py 

  real	0m0.023s
  user	0m0.011s
  sys	0m0.011s