InFamous (and the apparent re-casting of Cole MacGrath's voice actor) it would be completely logical to assume that Sucker Punch is working on a sequel to its electrified superhero sim. Therefore, one might also assume that the company's recently posted job listing, which requests the services of a network programmer who has "experience building on-line components of video games," means InFamous 2 will have some form of online mode.
We know, we know -- that's a whole lot of assumptions. Still, we're sticking to the old adage of "when you assume, you make an ass of you and me, but sometimes, you can totally predict things before they happen by simply making an educated guess." We'll contact someone over at Sucker Punch to try and help our chances.