Pretty messed up seeing people discussing Ethereum on here from the point of view of "coin and profit," instead of "platform and possibilities." I guess it's mostly the same newbies that still see Bitcoin as just a coin/commodity to invest in, and not a financial platform to develop on top of. Personally, I would invest 20BTC in things like BitMessage and OpenTransactions, despite their "coins" themselves not having any value, just because the possibilities they offer as platforms are enormous! I will be investing in this as well. Not because of the possible return on the coins (though I suspect that will still be substantial), and not even because of the initially proposed technology (which, as someone pointed out, is similar to some other coins out there), but because of the team involved. Ask any top VC out there. They don't invest in ideas, they invest in people. It's also why Bitcoin will always be top coin, despite other altcoins constantly coming out with little fixes here and there. The quality, and quantity, of people working on it is way superior to any other alternatives.
As for PoS, I really hope Ethereum doesn't take that route. PoW "decentralizes" the act of securing the currency from the currency itself. With PoW, I have a choice to either invest in the currency itself by buying it directly, OR invest in securing the currency by using it to buy mining hardware. There is also absolutely nothing to prevent a new miner from entering and competing with others, regardless of how many coins others hold. As a wealthy coin holder, I can't prevent a PoW miner from coming in and continuing to enforce rules on how I can spend my coins. The most I can do is spend some of my coins to buy some hardware and join him.
PoW I think you meant POS, on the other hand, incentivises, and in fact directs, the flow of money to one or few people, since you invest in "mining" by holding the coins themselves, and continue to increase your wealth by having those same coins collect even more coins. Threat of 51% in PoW is quickly resolved by having miners switch pools and redistribute themselves. Threat of a 51% in PoS can't be fixed by having mining wealth redistributed. Worst case end-game scenario in PoS is wealthy PoS miners continuing to accumulate wealth until they get a majority of the stake, while allowing users to become more and more dependent on their PoS coins, then the wealthy few pool their resources together, create a single, completely controling PoS stake, and change the coin to do whatever they want, including causing it to inflate. If you think PoS owners will be incentivized not to inflate away their wealth, think again. Central Banks around the world are PoS systems, and they do just that, printing more and more to buy up more and more assets, while letting those they sell their inflating money to pay for the inflation.
To me, POW is such a waste of resources, we are spending millions on resources to mine BTC, it doesn't seem like the direction we should continue heading as the world struggles with limited resources. The amount of power wasted mining BTC is absolutely atrocious. Regarding your concerns with POS, read up on Transparent Forging. POW is completely susceptible to corporate control, look at the mining pools, you are close to 51% with Ghash.io alone. Meanwhile I'm forging Nxt right now on my RasPi.
