"Cortana" last night; I found her and called it a night. It took me an hour and a half to get up to that point in the mission - and I was loving it. The new tactics the Flood exhibit really come into play more and made for a tense, challenging fight through the muck. A few standout moments -
--Climbing the first big ridge, at the crashed Pelican. There was a huge throng of Flood at the top, but they would swarm in and attack in waves - but they pulled back every time I took out a few, trying to lure me in. One of them was an Elite with a Gravity Hammer, the bastard. He took me out a half dozen times. They no longer do the straight rush, but rather fall back and hide, waiting to pounce. Sneaky.
--Pinned down by scads of turret forms, and diving from one point to another, dropping deployable cover and bubble shields along the way grabbing ranged weapons. I've read lots of people having problems with these guys, but they take about one second of plasma or spike fire, or two Brute Shots, and they fold up. Not bad, I just had to be careful as hell.
It sounds like this is going to be Halo 3's Library, the level every one hates, but I actually find it to be one of the best in the game. Very different, challenging (for the right reasons), with a gorgeous-yet-icky visual style and great atmosphere. The Flood are a smart, overwhelming challenge in this game.
My single biggest issue with Campaign so far: no three-way battles. Those were some of the most memorable set piece fights in the first two games, and the new enemy AI for both the Covenant and Flood would make for some spectacular ones. I don't understand why they were not included.
