As some of you might know, yesterday a link was posted from an Australian game news site about some of the new features that will be in Saints Row 2, according to them.

Today G4TV made this official by announcing it on AOTS in their The Feed segment.
Link to the page: http://www.g4tv.com/thefeed/...

So it sounds like you're going to have the option to play the entire Single Player storyline with someone else over XBL or playstation online. Also you'll be able to play the "open-world competitive multiplayer mode", and the name says it all.
You will also get the option to choose your gender (male, female or maybe a little of both?), voice, crib and even gang.

This game will for sure not come out before GTAIV, but it is scheduled for 2008, which makes it a must buy for me.
Just knowing that if I get stuck in a mission to the point where I can't beat it no matter what, I can just get a friend to help me out over XBL.