I have recently started learning Python and thus have learned that Ubuntu (10.10) uses Python 2.6. It seems to me that Python 3.X is still rather unpopular in the Linux/Ubuntu community.
Why is that?
Edit April 30, 2012
Python 3.2 is not shipped by default in Ubuntu. There are plans to make Python 3.2 default in 12.10, however, and make it the only version shipped by then. Python 2.7 will then not be on the default ISO anymore. Note: this is only envisaged, not certain yet.