Just like gold, bitcoin can be used as both a store of value and as cash. However, until the speed of transactions is increased dynamically and the increase in unanimity is assured, bitcoin will not become dominant coin of choice for John Q Public. For those reasons, I believe that bitcoin will, because of it's network effect, continue to be the dominant coin of choice for investors, those who are new to cryptocurrency and those who want to pay for high value items. Until bitcoin becomes more like Dash or Litecoin, it will NOT become the coin the public uses the most in day to day business. To me that's great. I like the idea that there will be more than one MONEY that is used all over the planet. UNTIL bitcoin or some other coin becomes the BASE or Reserve Currency to which all others are valued against, NO cryptocurrency will replace FIAT or government issued currency. Mark my words; the central banks will issue there own digital currency. Once that happens, all cryptocurrencies will then have a fight to become the dominant money on the planet. As far as gold vs cash, a fully developed cryptocurrency has the potential to become used as both, but we are a long way from that happening. IMHO

Far in the future I think we will see bitcoin server as gold and some other alt coin like DASH or Litecoin serving as quick spending money.  

IMHO unless bitcoin can get its act together, it will ultimately end up as a vehicle of long term storage of value, transfer of wealth, and payment for large value items like homes, businesses, insurance payments and the like. Bitcoin works great, as is, for those purposes. Dash and Litecoin would be great as day to day spending tools. Both Dash and or Litecoin will be valued against bitcoin or gold instead of Fiat. Each coin will serve its unique role. Gold/Bitcoin shall be the Base, Dash/Litecoin shall be the currency used to buy goods from the grocery store. Ethereum will be the mechanism driving and controlling the business world. All other altcoins will be valued against Gold/Bitcoin.

Once we start valuing ALL altcoins against bitcoin or gold, we will truly see the value of bitcoin stabilize and become rock solid.