Since I've been getting a lot of people asking about this. Yes, Ren'Py is going to be ported to Python 3. That will very likely take place later this year, or early next year, once the OpenGL Rewrite that I'm working on is mature enough that I can spend some time on something else.

My goal is to keep releasing a Python 2.7-based Ren'Py 7 for several years after that, to allow older games to keep working on newer computer. At the same time, I'll to release Ren'Py 8, based on a Python 3.x version, for newer development.

It's important to realize that Python 2.7 will not stop working in 2020 or anytime soon. The games that work today will still work today, and new games created with Ren'Py 7 will still continue to work. Many of the advantages of Python 3, like unicode strings, have been adopted by Ren'Py. So while this is something that I plan to do soon, right now I'd like to focus on work that more directly improves what Ren'Py is capable of. (And to be honest, to focus on something I'd enjoy way more than getting the Python 3 stack up on a bunch of unsupported platforms.)