Paul,
there are only very few companies that have public information available from "back in the day"... one of them is Private. Their 1997 numbers were not good at all. And they never really got much higher than that.
I know the other companies you mentioned. Playboy, yes, revenue wise very big... employee wise very big, but profit margin was always horrible.
Penthouse, went bankrupt in what, 2003? And not because of online porn... Also, New York Times quoted Guccione in saying the company grossed 4 billion USD in its lifespan... on avg that would be 133m per year. Net income half a billion USD, avg a year only 17m! Again, not big.
Vivid, Forbes Mag estimates Vivid's revenue a year at 100m USD. Although I do not believe this ever was the case, it again is not horribly high. I am again sure their net income margin was horrible even if this is true.
Northern & Shell, sadly not much public info, but the sale of their adult mags did not stir much, so could not have been so big.
Magna (Swank), very little info sadly, and I know little about their history, so...
Score Group... no idea in terms of size, lots of content though...,would love to buy them, so if anyone is reading this, talk to me!
David Sullivan and David Gold as far as I know owned Goldstar, so you listed Sullivan and Goldstar seperately as if its two things.. but I might be wrong here of course... again, very little info, considering David Gold sold a charter airline for just 4.4m pounds a few years ago, his porn stuff must have not really made him that much money <G>
Paul Raymond Publications was 19m profit in 1999 according to the guardian. The guardian also claims in 2001 it released 8 of the top 10 mags in UK, which would hint towards those other companies like Goldstar for example making less than Paul Raymond...
So all in all, I am not finding anything huge as you keep claiming... that is much bigger than anything online....
LFP is the only one I am horribly unsure about... but MOST of those, I would have bought for 110m easily (I did not buy Mansef for 110m USD btw). 110m would be way too much for most actually in my opinion.
BTW, regarding your wisdom about alexa stats....
http://siteanalytics.compete.com/pornhub.com+tube8.com/
Also, brazzers.com might be dropping in traffic, good thing we have more than one site and good thing we learn more about conversion every day