I have to admit, in spite of myself, I felt some compassion for Viserys there at the end. i felt it in the novel too, when he says, "That's all I wanted, what was promised" it's hard not to feel a sense of pity for him.
In other news, Tyrion is still awesome, and isn't there some big enormous Wall of Ice in this story? When will we be seeing that again?
In the books, he is about as irredeemable as can be - I'd use a lot stronger language for him if it were allowed. Major-League @#!%
It was pretty clear in the books that he completely misunderstood the Dothraki culture and became a pathetic character, not even worthy of pity, only mockery.
I think he is there only to show how much Dany matures and grows - she feared him her whole life until after she was wed to Khal Drogo.