Time to time friends forward interesting articles about the writing profession. Just got sent this one by Joe Konrath about the difference between potential earnings of Self publishing vs AAP publishers. Its about a year old but if ya haven't seen it and are considering the SP route might want to check it out.
http://jakonrath.blogspot.com/2011/02/numbers-game.html
http://jakonrath.blogspot.com/2011/02/numbers-game.html