What's with the breakdown of military discipline? Shaggy long-hairs in the marines?
Anyway... Microsoft/Bungie really screwed the pooch with the Halo universe. It came up in the ODST thread, but Halo showed much promise after the first game and the two Nylund novels set immediately before and immediately after. You had the overwhelming force and technology of the Covenant, a strange but deadly lethal parasite in the Flood, a sense that there was more to the story than the eye could see, that there was some sinister motive at work within the Covenant leadership, perhaps something known only to the Prophets. You had the sense that mankind was completely out of its league in the battle, yet the second novel especially allowed glimmers of hope.
And then Halo 2 and Halo 3 happened, and the Covenant never proved to be anything more than a doomsday cult.

Yeah, the games are fun, but there is absolutely no point to further universe exploration. Maybe one day there will be a sequel to Halo 3 that unveils a larger purpose to the Prophets' workings, but I just don't know if they're up to the task.