My experience is that sales of DVDs and videos have declined a lot in the last year or two. My income from them has pretty much halved each year. IMO it has got to the stage where it is not worth putting up the links for 20% of a $10 DVD, when you could send that person to a membership site that pays you $35 with a similar conversion ratio.

Watching online seems much more popular now. Which is a little odd considering such a small percentage of people have broadband so far.