The Thing and the Torch were easily the best part of the movie. They were perfect. The rest ranges from mediocre to poor.
The effects were good, but the script was awful.
Gruffud was decent, but had no chemistry with anyone else. Jessica Alba was just a pair of boobs. Nice boobs, but little else. There ain't no acting there.
Doom sucked. Big time. These jerkasses just do not get one of the best villains ever created? WTF? You want to see how to do Doom correctly? Watch the original Star Wars films. Vader IS Doom. Period. (and that's a rare moment of praise for Lucas from me)