gistfile1.txt

dudley@perks ~/Desktop :> cat parsedate.rb  
require 'date'

10_000.times do |i|
  Date.parse("2010-01-01")
end

dudley@perks ~/Desktop :> rvm 1.8.7,1.9.2,rbx-2.0.0pre exec time ruby parsedate.rb

real    0m2.894s
user    0m2.840s
sys     0m0.024s

real    0m1.721s
user    0m1.686s
sys     0m0.033s

real    0m9.086s
user    0m10.969s
sys     0m0.142s