I love the way Sasuke has been developed as a character! Betrayed by the only Uchiha he truly loved and trusted, Sasuke has grown up with nothing but hate in his heart...he only lives to kill Itachi.
It's so sad how he said he was willing to let Orochimaru possess his body if it meant he could kill Itachi....it shows how little he values his own life.
Some people say he's a cold menaie because he keeps trying tos hut Sakura and Naruto (especially Naruto) out, but I think he's only doing it because he can't trust himself to truly care about someone...not just ebcause it interferes with his goal, but because he's worried they will get hurt in the process.