I think a large part of the problem is that there aren't strong incentives to switch to Python 3, or at least that was the case when it first came out, and first impressions tend to matter. To me, as a user, it looked like "slower and none of my libraries will work."
A better way to sell python 3 should be to highlight python 2's pain points, and show why 3 is better. If they were to show a significant performance gain over Python 2.x, or some sort of killer new feature (ie, get rid of "self" everywhere) I suspect python 3 would get a lot more traction. As it is, Python 2 as a language works just fine for me, and most of what I want (a better interpreter) are being addressed by the PyPy project.
A better way to sell python 3 should be to highlight python 2's pain points, and show why 3 is better. If they were to show a significant performance gain over Python 2.x, or some sort of killer new feature (ie, get rid of "self" everywhere) I suspect python 3 would get a lot more traction. As it is, Python 2 as a language works just fine for me, and most of what I want (a better interpreter) are being addressed by the PyPy project.