Chris O'Dowd's character
This guy seemed more miserable before he lost his arm, then when he loses it he starts cracking lots of jokes. I don't think I've seen anyone handle the loss of a limb so well.
At times it felt like he was still on the IT Crowd, and he ended up being too humorous a character in light of the serious events going on.
As for being part of the Cloverfield universe; did anyone else find this to be more like Event Horizon? Even the tall blonde reminded me of Joely Richardson.