When Mark Millar was hired as a consultant on all of Fox's Marvel based movies, we pretty much figured it was because the studio wanted to bring their various properties together in a shared cinematic universe akin to what Marvel Studios have done. This was assumed, but never officially stated and Millar's exact role was not defined, until now. In an interview with SFX the writer says that Fox do indeed intend to "build a cohesive universe", and, he says he would personally love to see this working alongside Marvel's own cinematic universe - "It would be cool if these universes didn’t contradict each other so if you went to see Spidey, The Avengers, the X-Men, etc, as a viewer you would have no idea that all three are coming from different studios. I’d love to make it look like they’re all just happening in one place." So can we expect to see some of these characters cross-over in the next batch of movies released under Millar's watch? Well, not so fast..
“I don’t think it’s something anyone would want to rush into. Following that Marvel model, we want to establish things first. If you had a Fantastic Four relaunch, and Wolverine and the X-Men were in it, I think it would distract you from the Fantastic Four. You can make people aware that they’re existing in the same universe without making it a big crossover movie but it would be an injustice to the Fantastic Four not to make their first movie all about them.”
It may just be wishful thinking, but could you imagine if one day we had every single Marvel character on screen in a shared universe, even with the rights being held by different studios? Anyway, first things first, I'll settle on the prospect of seeing The X-Men take on The Fantastic Four for now!