[jampa]

Answering directly to the question: no, both languages coexist for so long. I don't see "Python killing Ruby".

Learn Ruby if you want to get started in web development, most of Ruby development projects is based on Ruby on Rails, and as a beginner is VERY easy to get started, you will get things done very quickly once you set it up.

Learn Python if you want to do... well, between the two of them python is way more popular in everything but web development. There's web frameworks with Python but I wouldn't recommend them for someone who is starting now (personally, I gave up on Django for Rails).

Nowadays it is better to start with javascript. It's not "beautiful" like those two languages, but is very forgivable and node.js is all the hype right now.