If you don't already know Python, it is still a good skill to have. I love going back to it for quickly prototyping algorithms sometimes, manipulating some files, or other scripting needs.
Outside of that, how it fares in the science community and enterprise, I can't give much insight.
The version shouldn't matter too much until you have a need for hardly maintained, very specialized libs. The big stuff usually works with Python 3 these days.
[1] I'm absolutely not a fan of tackling something with a steep learning curve without help. (As in I know I'll learn QT, C++ and windows programming at same time)
Python is a fine choice. And it's easy to learn. The difference between 2 and 3 is basically immaterial, but 3 has more interesting features to play with ...
I spent a lot of time on Perl, and I have a solid understanding of basic programming (functions, objects, loops, recursion, iterators etc ...)
In many project, we just need sometimes to create a small data entry program
I need either a language or a framework, that will allow me to easily create few entry screens
MS Lightswitch would have given me what I needed, except Microsoft seems to have abandoned it (At some point in time I learned enough C# to manage my way into lightswitch)
Anyway, I thinking Python's PySide might be a good option for me, since Python seem also big on Data Analysis (which is something I do a lot) But I am also checking iDempiere and Netbeans, Eclipse as possible database GUI platforms