First of all I have to give props to 343. I was blown away by this game, you guys worked your -Yoinks!- off and it shows. That being said, there are a few things about the story that I would like to discuss.
Can we say now which Didact was sealed in Requiem? Based on the description of Selentium and the terminals, I believe it to be the Ur-Didact. Anyone else agree/disagree?
Also relating to the Didact. If his plan was to turn all humans into AIs via the Composer, what happens now that it is seemingly destroyed? Does he try to activate the Halo Array as a last resort revenge plan? Furthermore, is it possible that he was turned when he fell into the beam?
What role will the Librarian play in the coming games? Maybe shes not really dead, and there are fragments of her out there, like Mendicant Bias.