Disclaimer: This is very subjective and from a Python guy

1. While Python and Ruby are roughly of the same age, Ruby was only popular in Asia before Rails. At that point Python already had a solid base of non-web stuff.

2. Ruby feels more wild and crazy to me. Is monkey-patching still considered cool in the Ruby community? As a Pythonista I try to avoid such confusing stunts.

Due to both of those reasons I believe Python has more solid libraries. For example, Rails was extracted from a small productivity app, while Django was extracted from a serious newspaper website. While Ruby was fixing memory leaks, the Python interpreter was speeding up its hash map.

As a language enthusiast I envy Ruby for the blocks. As a Python programmer I never felt the need for them.