Each crypto has its own unique properties, so both represent strong investment potential. I agree with the premise that ETH's market cap will exceed Bitcoins before 12/31/17. Functioning as the foundation for numerous new programs and cryptos, ETH will be viewed as the "cool new up and coming crypto" on networks likes MSNBC and get pumped. Although Bitcoin will lose market share to ETH and other cryptos, it may very well remain the basis for which all others are valued...similar to the gold standard. Because of this, my take is: you're poised for a win win if you HOLD both for the long term if you can manage.