For those of us that saw Thor and couldn't wait to discuss it with friends, family, and random strangers on the bus, there seems to be two very distinct teams among us: those who love Loki's character, and those who can't wrap their heads around why he did any of it.
 
Let me give you one word: attention.
 
Older siblings have an advantage--they are generally bigger, stronger, and not always used to sharing.  Many of them are big personalities of varying degrees of malevolence.  Are you one of those older or only children?  You probably have a harder time figuring this villain out, just like my older brother.  But let me tell you, there is some rhyme and reason to his antics.
 
Now, we're talking about movie Loki, not comic Loki, who began life several decades earlier and suffered the same problem that most other characters did back in the Golden Age--simplicity.  If we're going to discuss his character, we better make sure we know which version we're talking about.
 
Roughly put, movie Loki doesn't start off a horrible person.  He's not out to overthrow Asgard, he's not out to murder his father.  (Quite the contrary.)  What he wants is the attention and control he feels he's been deprived of in his life.  Add to that Thor's general recklessness, which undoubtedly grates on calculating Loki's nerves.  Pile on the fact that they're princes and by birthright should be the ones making decisions.  Loki is discontent in this rut of status quo and being the tagalong to big brother, tucked into a corner without being told why.  He wants to shake things up a bit.  He wants to taste that control and just do whatever the heck he wants for a while.  So yeah, he's a little jealous of his brother.  It sounds almost reasonable, right?  No?
 
What about that kid in class who acts up because he doesn't get enough love at home?  Now does it sound plausible?
 
His slide off the deep end really starts when he has his identification crisis.  Now, not only is he the tagalong, but a monster he's grown up fearing and hating his whole life.  Now it all makes sense!  But even then, hurting his parents and destroying Asgard were not his goals.  Now he just had even more to prove, and eliminating his competition was a good way to do it.  Thor and the frost giants had to go.  And when that didn't work, Odin's disappointment was the final straw on the camel's back.
 
If he can't have good attention, any attention will do.  And people always notice villains.  And the solidified bitterness in Loki can finally rear its head and do the things it's always wanted.
 
Long story short, it's a little in Loki's nature to be a bit selfish and sneaky, but his circumstances didn't help.  This is the result--a psychologically-complicated character I hope will continue to strut across the stage doing his thing for a long time to come.  Your thoughts?