I used to play dudes all the time because I am one and this made it more 'me'. Ever since Commander Shepard though, I play as women wherever I can. If a game doesn't give you a choice, chances are you're going to be playing as a man, so when there is a choice it's nice to address that balance a bit.

The only exception was when I was playing a bit of FFXIV. I don't like having people assume I'm a woman just because that's what my avatar is. Mainly 'cause I've done that before and then they feel all betrayed when they come on to me and I tell them I'm a guy.