Now is a good time for a sequel to come out, with everything that's been going on past couple years. AP2 would have plenty of material to comment on or poke some fun at. Plus there's even more interesting, cool, & wacky tech to work with. Robo Cows + Heck, something needs to happen.
Sega. They seem to be trying something new with Creative Assembly, if that works out for them maybe they'd consider more AP. Can't be more risky than an Alien game right after CM, right?