Ethereum was doing very well before DAO coding mistakes happened. I was against the hard folk for decentralized reasons, but ETC happened right after... We will see in the future what will happen. I would hope for ETC to go away to be really honest.
Bitcoin is necessary, we need that coin to act as a PURE exchange agent. Ethereum is much different and should not be only considered as an exchange agent (even if it is of course!).
Great article!