My personal theory of "why python" is that it broke with the unixism of recycling syntactical conventions. While the conventions were useful, the line-noise aspects that were perpetuated turned a lot of people off as unnecessary obfuscation. Python was more than a clean break from that, it was pushing towards actually trying to enforce a certain amount of readability.

I default to python for scripting at work because it is popular - we are more likely to find folks who have at least seen it before. Most of my throwaway and experimental code is Perl5, just out of long habit.