Take a look at these quote from nearly a year ago:
Dude the hashrate is about to level out
What is nearly impossible to predict is WHEN it will level off. It seems to be starting to now, but this could be a hiccup.
Go look at the network hashrate back then compared to now. Anybody predicting the hashrate is leveling off is going to look like a fool in a year. Just like those guys look now.
here is one prediction that will hold true: IF BTC goes to $100 (<10% of peak similar to 2011) THEN hashrate will not only level off, but decline (not that I am seriously expecting such developments to occur).