I use both Komodo Edit and Notepad++.
Notepad++ is a lot quicker to launch and it's more lightweight, so I often use it for quick one-off editing.
I use Komodo Edit for major projects, like my django and wxPython applications. KE is a full-featured IDE, so it has a lot more features.
Main advantages of Komodo Edit for programming Python:
- Manage groups of files as projects
- Use custom commands to run files, run nosetests/pylint, etc.
- Auto complete & syntax checking
- Mozilla extension system, with several useful extensions available
- Write macros in JavaScript or Python
- Spell checking
Some of the little things that Notepad++ is missing for Python development:
- Doesn't auto-indent after a colon
You can't set tabs/spaces on a file-type basis (I like to use tabs for HTML)
No code completion or tooltips
- No on-the-fly syntax checking