From what I'm reading here, 343i is going to need to do a HELL of a job on exposition for Halo 5: Guardians.
They can't afford repeat Halo 4 where they introduce a major antagonist with barely any explanation about who he is, besides "He's in the books!"
Especially now, since they've effectively tripled their work. They've gotta introduce new players to:
Agent Jameson Locke (For those who didn't watch Nightfall or play Halo 2 Anniversary)
Blue Team (Fred, Kelly and Linda have been known to Halo geeks for ages, but their not known to the general population, a failing of Bungie's Halo era I'd say.)
Locke's Fireteam (Romeo, Buck, Tanaka(?) and/or Macer(?))
I hope they're up to it. I want to give them the benefit of the doubt, going by how well they've merged expanded lore with the Hunt the Truth podcasts, but ... I'm still worried.