So,
100k views - 1 day , 300k views - 7 days . Difference 200k views over a 6 day period so that is 33k views per day versus 100k per day
850k views - 30 days , means 850 - 200 = 650 over 30 - 7 = 23 days so that is 650k over 23 days = 23k per day ...
100k = 10 sales, that is one sale in 10k, 15 sales over 850k that is 1 sale at 56k views which is quite good I'd say given the current times and the fact that is probably on a free porn tube.
Keep in mind how many of that 850 are unique...
If you want the theory start here :
http://en.wikipedia.org/wiki/Long_tail
by the way, I love your post and how you actually ask the right questions, from a program owner point of view...