seeing as how the last few jumps were on the order of 40-50%, this is a welcome change. It also tells us that expected mining profitability is quite low, but still positive as people are bringing some added capacity.
Well, at current bitcoin prices, mining profitability is quite high. So if what you say is true either people are betting on big price drops (in which case they're also betting on bitcoin failing) or this is a retraction as people feel the sting of their gold-rush calculations biting them in the butt after the drop from $32 to $14. Those aren't really well thought out analyses though.
I'm guessing people are just adding more cautiously now, instead of sinking $10,000 - $40,000 at a time, as fast as possible, as recklessly as possible, expecting to have money rain down on you, people are looking for efficient building and taking it slow so as not to lose their families if things turn sour. This is prudent.
Yep, people are just taking it slowly because hardware doesn't pay for itself in 3 weeks at current price levels anymore. And I think the reason a lot of people are mining instead of buying bitcoins directly anyway is to hedge their risk - if bitcoin takes a dump, they still have computer hardware they can sell to recover some of the initial investment. So, theoretically, it could be said that miners are generally risk-averse. When the profit margin for mining slims down, and high volatility still exists in the market, to where a miner might not even be turning a profit mining by the end of the week, and being that a miner is risk-averse in the first place, they're probably just in a holding pattern to see what will happen next.
Theoretically, you could buy hardware and still have it pay for itself in a few months, which is still an extremely good ROI, but you can't count on those future profits anymore, unless you're a risk-taker.
Just approoved a 75k USD purchase plan 
