[Baypiggies] Python 3 and the GUI - opinions wanted

[Martin Falatic]

When it comes to creating a modern GUI-based, cross-platform application
in Linux/Mac and Windows using Python (and taking Python 3 into
consideration, with Python 2.7 as a backport path) what's is the best
direction to go in? Tkinter, PySide (Qt), others?

I've found some discussion on the topic elsewhere (e.g., Reddit) but I
wanted to get the opinion of developers in our group here.

Regards,
 - Marty