Honestly? GPU mining will die out, *probably*. Why?
- The big ASIC's for scrypt are arriving, Scrypt-N is not popular enough, and there are rumours about X11 FPGA's. Sidenote: GPU's are adaptable. If for some reason, the next popular coin, like LTC/DOGE, arrives with a new algo that is cool in both ways, a gpu miner will be able to switch to it instantly (well, as fast as a dev can work and release their work
)
- Mining isn't as popular as it used to be, but this could change if BTC has another big pump. Sidenote: Some miners will profit from the much lower hashrates, but it is volatile: as soon as it becomes really profitable again, all those sleeping rigs will be awakened again. I guess there are loads of people with GPU's they cannot sell.
- Pure PoS is running rampant these days, lead by BlackCoin, so no more mining required. Sidenote: Most pure PoS still have a few days to weeks with classic PoW for initial redistribution, so I guess some miners will stick to the game of mining every new coin
- Mining with PoW isn't eco-friendly at all. In our age of global warming, isn't this something we should think about?
So, GPU mining, in my view, will die out, except for the hobbyists, like it was before they/we ever heard of a BTC/USD exchange