We think altruism isn't a good model -- people aren't willing to pay for things which have already been delivered (e.g. content). This is why we're starting with bounties.

The title of this submission is a little misleading - when you upvote an answer on Cent, you're effectively allocating a portion of the bounty to that answer.

re: Ethereum. We definitely think there is huge potential for decentralized apps (dapps) and that Ethereum is at the forefront of making them happen. One HUGE barrier to adoption is that, aside from maybe having a gpu that can mine a tiny bit, your only gateway to getting Ether is by buying it, e.g. through Coinbase. Without Ether, you can't use any of the dapps, and if it's just a bunch of speculators holding Ether, the dapps may never gain traction. Fundamentally, we believe that currencies are meant to be earned, and we want to be a mechanism for people new to the decentralized world to get involved by earning them.