I care about seeing Python 3 succeed and pushing against the FUD that some spread about the lack of Python 3 uptake since I am on the Python development team. That means I am willing to put in more time and effort into manually updating information than others. I am also willing to put up a little bit of my own money to make sure this web site updates on a daily basis so as to always have the freshest data possible.
You can send me a message through my Google profile.
The low-end of the percentage range only counts projects that have released a version of their project with Python 3 support. The high-end counts projects that have Python 3 support in development.
It's a visualization of the percentage range of projects supporting Python 3. Projects that have Python 3 support under development only count as 0.5 of a project. And yes, I realize the colour-blind might not see much of the colour, but the same information is shown as a percentage and the list is right there so no one is being excluded.
Georg Brandl has a chart that shows the number of projects over time that specify Python 3 support in their trove classifier. Unfortunately because it requires project owners to set the proper trove classifier it is not highly accurate, but should give a good trend indicator of Python 3 support in the community.
Set your trove classifiers for what versions of Python you support, please! Even if you only specify Python 2 support it helps me out.
You can check to see if any project that has been flagged as not supporting Python 3 manually (i.e. metadata rating is 2 stars or less) is actually now supporting Python 3 or it at least is under development. Otherwise if a project has 3 stars or more for its metadata you can check if the project is actively developing Python 3 support. If you find out any project is mis-marked, then contact me.