1.The difficulty is starting to have huge increases again while the price is going DOWN, it already is below 300 !
2.My estimate is that next difficulty is going to be above 15 % and the others following will be somewhere around same level !
3.Soon NEXT GENERATION ASICS will be launched and the difficulty will start raising even more, we might see 30-40 % + increases in difficulty,
and the miners we bought now will be absolute, with no chance to EVER ROI.
With all these, let's just ask ourselves:
Is it still worth mining bitcoin right now ?
It's hard to say, people were thinking the same thing when the price of BTC dropped out of the $600 range and difficulty kept going up as more mining started up. One thing that I noticed is that even with the lastest asic miners, the power requirements keep going up with it. So, I don't think until the power efficiency is addressed, that the next gen asics will really impact things. I stopped mining bitcoin alone back in March of last year and started mining altcoins and buying other crypto (ripple/stellar/etc) along with it.