Python 2 was released Oct. 2000 and so will have a 20-year lifetime now. http://en.wikipedia.org/wiki/Python_(programming_language)#H...
Ruby 1.8, which was retired last year, had 10 years of life: https://www.ruby-lang.org/en/news/2013/06/30/we-retire-1-8-7...
Obviously, version numbers don't mean the same thing...and Ruby 1.8.x to Ruby 1.9.x (or even 2.x) seems less of a jump than 2.x to 3.x.