Here's an 8 minute demo showing how to use the new TextEditor Quickly Widget. This removes all the pain and suffering of adding text editing functionality to your app. No more gtk.TextBuffer, no more gtk.TextIter. Just a series of simple function calls, and you're ready to go. Of course, TextEditor is a gtk.TextView, so if you need to access any of the power and flexibility of the underlying Gtk library, it's right there.
TextEditor is now available in quidgets trunk.
Sorry for the loudness of the video. I made it in a coffee shop, and moved my mic closer to compensate for background noise. It didn't work out too well.