That website is way way off when it comes to next estimated difficulty.
http://bitcoinwisdom.com/bitcoin/difficultyThat one is way more accurate, and adjusts every so many blocks.
Our longterm average increase from the genesis block is 15.42% per adjustment. For easy math, lets say 15.42% every 2 weeks, thats 30.82% increase every month.
The increases as of the past year have been greater than this though. Reinvesting the 35% they are, will have them barely keeping up with difficulty, however, I do believe that it will have to level off eventually. I have no clue how large the network will be, but the larger the # the more it will take to push it higher.
If the site you mention, which I know nothing about, is accurate, then this does present a real problem. Using a long term average is not useful for prediction of next month, but using data from Nov and Dec at the site you mention we can expect an adjustment per month of 40%+. That would indicate a real-value loss of 20%+ per month, and these values do compound over time.
While I think it is unrealistic for us to pursue a 100% compensation arrangement, including the fact that we do not know the details of that contract as rdyoung mentions, I do think we should pursue protection from loss of real value. Perhaps we can argue for treatment only half as good as this other person received, obtaining 50% compensation.
While I do not think anything will happen realistically, and while I think PETA is a good value at .05 regardless, as I said before I would be all the more pleased if we can leverage this situation into an improved deal.
I am using the longterm average because thats how I read data. The more info the better. We could cut everything out pre asic, but those increases wont affect the #s that much, so there is no need. We can't assume anything in the short term based on previous months, this is why I am looking at the long term average.
Changes in difficulty are likely tied to ship dates from the asic manufacturers. So if cointerra meets their deadline for jan batches, we will likely see a larger increase in feb as these machines are brought online.
Again, from a statistical standpoint, this parabolic rise can not continue. I am not saying it will stop tomorrow, but it will have to slow eventually.
Look at it like this. Assuming 10phs where we are equals 1.5billion in difficulty, to increase the difficulty to 3billion, IE 100% increase will require 10phs more of hardware coming online, if all the chips were cointerras 500ghs chips, 10,000 chips would need to come online. And this doesnt account for all of the older gens of hardware that are being made obsolete with every increase, nor the hardware that is likely dieing or being pointed at altcoins.