I am a leaner. for your experience. Which GUI Lib will be the bestI'm sure you'll get as many opinions on this as there are libraries.
for Python? wxpython, Tkinter or...
However, I recently faced the same choice, and settled on wxPython.
I've been very impressed with the quality and "nativeness" that's
achievable with wx apps. You'll find a number of demos with the
wxPython distribution (already installed on your machine, if you're
using OS X 10.5), and it's well worth running them to give you a feel
for what it can do.
In addition to the quality apparent to the end-user (which I think is
the most important thing), I find the wx API to be quite sensible and
easy to work with too.
HTH,
- Joe