I've read all the responses and I feel compelled to respond. Please don't bite my head off anyone, please, since I have a different perspective.
As a Physics undergrad and a computer consultant now, I work with men most of the time. And I kind of get in on the real scoop. I would say the majority of the men I have met (notice I'm not saying the majority of men in the world) including the men that I went to college with at a private christian school, were interested in porn.
In my opinion porn is out there, its a fact of life, and most men will look at it from time to time. Including movies, strip clubs and internet, especially the internet.
That being said, I'm not saying that all porn to all degrees is ok. What I'm saying is that its not the porn or the mere fact that someone is enjoying porn that makes it bad. I'm also saying that your husband is not in the minority I would think and because he looks at it, it does not make him addicted.
What's IS BAD are the comments your husband is now making about you not living up to the porn figures. That's just unrealistic and he is living in a fantasy world. He has crossed the line from just sort of being amused by the whole thing to actually thinking normal people behave in that manner.
I would recommend counciling for both of you. Clearly your husband doesn't feel like what he is doing is wrong and you do, and there in lies the disconnect. Also, by you forbidding it, it makes it that much more enticing to him.
From personal experience EVERYONE I have ever dated has liked porn, and I am not dating all completely godless people. The difference is I am open about it and so are they. They can tell me the truth about it and I think this actually serves the purpose of making it less likely that they will look at it. Its no longer a forbidden fruit.
I am married now and my husband can be totally honest with me if he wants to go to a strip club or on the internet. But the only time he ever goes is for a bachelor party or something along those lines. But he never has to lie about it and that creates a very honest open relationship. The guys I work with are always talking about their escapades at the strip clubs and how they are hiding it from their significant others.
Just my thoughts, please don't kill me.