Which IM Do You Use?

Which platform do you use for instant messaging? The three big ones are AIM, Gtalk and Facebook chat. I used AIM for a very long time but recently an employer wanted me to use Gtalk. I am starting to like it. I like FB chat as well, but not everyone is on FB. Yes, it's true, not everyone uses it!! LOL I use all three but I think Gtalk is winning me over, unless I'm playing Farmville.