Who out there is scripting in Python for their Macs?

Me!

What do you use it for that's better than using Bash for?

Anything slightly complex; anything dealing with arrays or structured data like plists or dictionaries; anything that needs to use Cocoa methods or Foundation or CoreFoundation methods.

Anyone move over to Python from Perl?

Yes, as well.

I second Greg here. I use Python for almost anything more complex than a simple if/then script. I use it for regular maintenance tasks, system configuration, and also have written a handful of extension attributes in it.