No, not quite that simple, since the total combined site membership is only a small fraction of combined total satellite subscribers, add to that, this site is geared a bit more towards Dish Network than DirecTV, along with other numerous factors, including the fact we ('we' as in non admins) have no numbers of which of these site viewers actually HAS Dish or DirecTV, i.e., I have D* but read and reply to the E* forums just as much, so all my reading of Dish forums might make it seem I am an E* sub, when indeed I am not, and I won't even bring up the forum hits gotten from Google search results, or the fact that alot of views are counted on those who are not even logged in here, or subscribed (so even if the admins gave us the data they had, it would never be perfect), then there's referrers from other sites, the average amount of technical curiousity of each type of sub (perhaps more provider-specific inherent saavy results in more views and posts?), the amount of problems associated with each provider (perhaps more problems attract more posts and views?), etc.
Just way too many variables for one to extrapolate actual subscriber growth data with any kind of accuracy, without a better formula.