I use pico to edit blosxom entries and write mail (since it's the editor behind PINE). I like it much better for creating paragraphs and sentences and such.
If I'm editing at a terminal for anything else, it's a vi variant.
For some stuff for The Perl Review, I use TextEdit because I need RTF, and I only need to write a screenful.
But what I really use is BBEdit.
What I really don't use is emacs. Randal does everything in emacs and constantly talks about how he'd like to dump Mac OS X and let emacs do everything. Okay, maybe he doesn't say that, but I know he's thinking it.