Re: THOR: Grading, Discussion, Review **SPOILERS***
I'm not up on the Thor comic continuity these days - is Loki being a frost giant from the comics, or invented for the movie? Or, for that matter, does it go back to the original folk mythology, about which I also know only the most general stuff?
Loki being a giant was in the original mythology. What they changed was him being Thor's brother instead of Odin's.
Live Long and Prosper