I've got a dual campaign running with a mate and we play together as Egypt every monday night. Not managed to get a really good single player game going yet but we've played over 100 turns on the Egypt game.
I really, really like it.
See maybe that's where I'm missing out as I haven't done a dual campaign yet. I generally just play and rate games on single player because I hate people and play video games to escape them.
Other than TF2 of course.