The final Twilight film hasn't even come out yet and they're already throwing around ideas of ways to keep the series going forever and ever and ever. As of now, it's just talk — Stephanie Meyer hinted that she might be open to writing more Twilight books, but she's yet to set commit any words to page. Then there's the willingness and availability of the actors. Leading haircut Robert Pattinson could potentially be interested if Meyer and Co. would be willing to make some major changes.
He tells Ellen:
"I was also thinking, like, another way to do it is make it a little bit like Will & Grace. Edward turns gay, but [Edward and Bella] still stay together and they raise the kid and everything."
Having witnessed the intense homoeroticism that occurred between Edward and Jacob during the Twilight: Eclipse tent scene, I've gotta say that this doesn't seem like too much of a stretch.