You are missing the other things he did. The messages he sent out to others, sharing the broadcast, sending out tweets, IM's, and more. His culpability comes not in recording the sex, but in distributing it and publishing it in a negative way. Just because you don't forsee the outcome of your actions does not mean that you are not responsible, at least partially, for the outcome.
I think the punishment is appropriate. He, and others and lets be honest punishment is about determent, will think twice about doing things like this because they don't want the news, the fines, and the jail time.
To be honest, if he had not been such a douchebag in court and in the limited time he was in public he probably would have gotten less. Hard to have sympathy for someone who was cold, calculating, and who's only response thus far has essentially been "its not my fault, I should be able to do what I want".