Voted: "Yes, I do this regularly when I'm alone"
It really helps me figure things out, to be honest. Like, from personal problems, to friend problems, to work problems, etc., it'll be some problem I can't quite get my head around, say it aloud, and then be like "Oh! Duh, that's obvious." As if just saying it out loud makes it immediately easier to understand.
Generally, if I say things out loud I can think of how other people might respond, and how I'd respond to their response. How I would respond is what helps me figure out and cement my reasoning behind things...
Also, the poll results make me feel a bit better about talking to myself haha. I knew others did it, I didn't think that this many did. XD