My order of dying at the end was this: Legion was sent into the pipe, but he survived that part without any problems. I managed to open all the valves with plenty of time left, I don't know if that had anything to do with it. However, Legion was headshotted trying to close the doors, and was the first to die.
Jacob was my biotic during the shield section, he survived. However, Grunt (one of my squad mates) got killed at the end. You know how pissed that made me? The one single purest krogan in the galaxy, gone.
Everyone else survived, only two people died. I assigned Zaeed to lead the first fire team, Garrus to lead the second one. My own squad was Miranda and Grunt, except after Grunt got killed, I replaced him with Tali. I did everyone's loyalty quests, though if I had to estimate I would say Legion is probably the one I talked to least. Not sure where Grunt falls on the scale.
The revelation of the human-Reaper was definitely a nice WTF moment. Appropriate, too. The Reapers we've seen so far are all insectoid, and the Collectors (and by extension, the Protheans) were insect-like. I'm guessing that after the Reapers' cleansing of the galaxy, they base their next iteration on the most dominant and/or worthy species they find during that pass. Also, I thought the tube-shooting fight was the final battle at first. I was all disappointed until a giant Reaper skull reared up and scared the crap out of me.
There were other nice WTF moments in the game. The revelation that the Collectors were once the Protheans caught me by surprise. The Collector attack on the Normandy was tense, I was so used to having a huge stockpile of guns on my back, getting used to running around without them took a bit of time. Mordin singing was also a WTF moment, but in a good way.
There were still some strange unexplained moments in the game though. Ashley survived my imported game, and she was at that colony that was attacked by the Collectors. We watched her get paralyzed, and everyone else was taken, so how did she survive? Also, I don't think the Reapers' fascination with Shepard is fully explained. Do they target him because they see him is a particularly dangerous threat?
Finally, I romanced Miranda during my normal play through. After completing the game, I had the option to continue playing, so I immediately broke up with Miranda and seduced Tali - mainly because I wanted to finally see what she looked like under that mask. Intimate scene comes up, Shepard removes her mask... and the camera immediately cuts away. FUCK THAT!!