This article contains spoilers for Immortal X-Men #5.
The X-Men's Jean Grey is becoming more important than ever before. The last few years have seen the freshly-resurrected Jean Grey claim her rightful place as a power player among the X-Men. The X-Men's resident Omega-level mutant left Krakoa's ruling Quiet Council to become co-leader of the X-Men, standing side-by-side with her lover Cyclops. The Hellfire Gala led to Cyclops and Jean learning just how bad things had gotten on the Council in Jean's absence.
According to Marvel, Jean will be one of the key figures in the current Judgment War event. It will include a one-shot, A.X.E.: X-Men #1 by Kieron Gillen and Francesco Mobili, which will finally reveal the true connection between Jean Grey and the Phoenix Force. It's already becoming clear the Phoenix will somehow lie at the heart of this story; Immortal X-Men #5 features a wealth of Phoenix imagery, and even ties another Omega-level mutant - the psychic Exodus - to the Phoenix.
Immortal X-Men #5, by Kieron Gillen and Michele Bandini, is focused on Exodus. Bennett Du Paris has always been portrayed as somewhat fanatical in his religious zeal, and the issue reveals he has reoriented his entire life around a mutant version of Christianity. He is particularly devoted to Hope Summers, who he still views as the "Mutant Messiah" due to her connection to the Phoenix. The recurring Phoenix imagery, coupled with the promise of Jean Grey revelations, suggests Exodus is going to learn he's wrong - and that the true mutant Messiah is in fact, Jean Grey.
It will be interesting to see where Judgment War takes Jean Grey's story. Some fans are speculating Exodus' mutant religion - which directly contrasts with Nightcrawler's nascent faith - will take shape over the course of the event, with a sort of mutant version of the Trinity - mother (Jean), daughter (Hope), and the Holy Spirit (the Phoenix Force). That would certainly fit with the religious imagery building up around Exodus, transforming him into a prophet of an evolving faith.
This is only a theory, of course. What is absolutely certain is that Jean Grey is becoming more important than ever; Emma Frost's words in Hellfire Gala #1 positioned her as the X-Men's conscience, and the Omega-level mutant will stand at the center of this ongoing story. It's only been a few years since Jean Grey returned from the dead (ironically, due to her strange tie to the Phoenix Force), and since then she's becoming the most important mutant of all.
Immortal X-Men #1 is available now from Marvel Comics!