Another thing worth mentioning is recurring payments. Many of these porn sites make money off recurring payments. Many people sign up with credit cards and then let it auto renew. None of the porn sites I've seen have a great way of renewing a membership with BTC. It's clunly.
Unfortunately It's hard for companies to understand that by offering Bitcoin they are getting NEW customers that they wouldn't have received before, not losing customers to a lower LTV payment method.
Auto-renewals are not possible if the payment is being done directly with Bitcoin. But it may be possible if BitPay or some other payment processor is being used. So it will be quite similar to accepting the payments with credit card. But I am not a big fan of BitPay, BTW. Previously they had refused to work with Colorado Marijuana shops, saying that they don't want to get associated with semi-legal business.