[davem]

The Azog thing became a lot clearer on a second viewing - its obvious that Thorin had convinced himself (consciously at least) that he'd killed Azog because Azog had killed his Grandfather & he had a duty to kill the perpetrator in revenge. The idea that he had failed to do so would have been an unbearable stain on his honour. Hence, he convinces himself that the blow he dealt Azog was fatal. Yet when he says that there's (unless my memory is flaky) a very doubtful look that crosses Balin's face (& Gandalf's) as if to say "Who're you kidding?" I got a strong sense that deep down Thorin doubted Azog's demise himself. Clearly this is a Thorin driven by a sense that he is not worthy of his inherited role & his failure to avenge Thror just adds to that. He feels he should have done that just as much as he feels that he is obliged to take back his Kingdom.

I think the fact that he has now taken Bilbo to his heart & feels him to be as loyal a companion as any of the others will make Bilbo's 'betrayal' of him on the eve of battle all the more painful for him - Thorin will feel he has finally achieved what he was obliged to do, attained to his birthright, only to be humiliated by someone he trusted & believed was loyal to him to the death. I think the end of this film has set up that event perfectly. I actually think that the fact that that confrontation & the final farewell between him & Bilbo has been foreshadowed by the ending of this one will add to the power of it at the end.