This page is a collection of feedback from the internet about the 5 years of progress in Python development. It is started to link from Python Planet blogs, but feel free to add more links to it:
http://blog.startifact.com/posts/alex-gaynor-on-python-3.html
http://strombrg.blogspot.com/2013/12/python-2x-vs-3x-usage-survey.html
http://programmers.stackexchange.com/questions/63859/why-do-people-hesitate-to-use-python-3
You can help to getting the whole picture by taking the survey put by Dan Stromberg: