Look at how slow Python 3 adoption has been. I don't think completely breaking backwards compatibility is a quick thing. The Python folks expected 5 years for Python 3 to become the default version because of the dramatic changes.
I've worked on a number of software systems at several different organizations that have very effectively used Python 3 for years now. I think that Python 3 has been adopted perfectly fine by many other people and organizations, too.
We're just not overly vocal about using it, because it has worked for us with so little pain and so little effort in many cases. It really wasn't much different going from 2.7 to 3.0 or 3.1 than it was going from 2.6 to 2.7, for example.
I've worked on a number of software systems at several different organizations that have very effectively used Python 3 for years now. I think that Python 3 has been adopted perfectly fine by many other people and organizations, too.
We're just not overly vocal about using it, because it has worked for us with so little pain and so little effort in many cases. It really wasn't much different going from 2.7 to 3.0 or 3.1 than it was going from 2.6 to 2.7, for example.