It gets exponentially harder, the power required now has gotten insane. I saw a presentation by a guy that runs a huge mining operation here in the US recently, and he said they were burning 50 gigawatts. Also, he mentioned that the last few percent of bitcoin was going to take about 100 years to mine because of the complexity level. I think we can assume computers will get better, but it's kind of crazy.
The fact that it will take maybe 100 years to mine the last few bitcoins has nothing to do with the complexity / difficulty level. This is caused by the block reward halving schedule. The increase in network difficulty only makes sure that bitcoins don't get mined ahead of time, regardless of whether hardware gets better.
Oh yea, now that you remind me, he did talk about that. The mining side of the equation is new for me. He'd also made an interesting comment, I'm curious your opinion. He said that a PoS Ethereum will never happen because the miners won't agree to the code change since it would kill their operations essentially.
I don't follow Ethereum all that much to be honest. My educated guess is that miners will have little say in it and that PoS Ethereum will come sooner or later. Question being whether ETH miners will simply point their hashrate to ETC or whether we'll see yet another Ethereum hardfork.
