This could be either absolutely amazing or monumetally terrible I doubt there will be just an okay result from this.
I hope they don't try to continue the story from where it was left. It would be cool to see some branched side story games or on the timeline from before the original game.
And if anyone wants more Halo, read the books, they are great and let you know more about the characters. A great deal more actually and lets you know there is so much left to be untold or delved into in new titles; movies, books and games.