Guerilla Games is best known for its Killzone franchise, and today it looks like they may have plans to expand the franchise to incorporate open-world and RPG mechanics in a future title with the hiring of John Gonzalez, who served as the lead creative designer and lead writer of Fallout: New Vegas.
Gonzalez's LinkedIn profile has a confirmation that he was hired by Guerilla Games in September (via GI.biz), leaving behind his lead designer role at WB Games where he was working on an unannounced project. As the profile notes, Gonzalez spent more than two years at Obsidian Entertainment on Fallout: New Vegas.
His profile page suggests that his "focus is storytelling for open-world role-playing games. Because they are awesome," which indeed they are.