Ridley Scott confirmed months ago that the script to Prometheus 2 was in the bag. Filming is slated to begin this fall, with a projected release date of March 2016. Now, in unsurprising but auspicious news, Michael Fassbender has confirmed he's "doing a sequel," presumable reprising his role as David (Davids?).
Fassbender's confirmation came during an interview with Collider while promoting X-Men: Days of Future Past:
Regarding the specific exchange on Prometheus 2, Steve asked Fassbender if he was looking forward to working with Scott on sequel, and he replied, "For sure. I love Ridley. He's a master filmmaker," at which point James McAvoy, who was also part of the interview, turned to Fassbender and asked, "Are you doing a sequel?"
Fassbender turned to his X-Men co-star and replied, "Yeah, but when I don't know."
More at Collider.