bitcoin itself as a protocol will evolve.Many people forget the simple fact that it is a protocol first and the money part just happens to be the first app written over it. thinking of it like the Netscape browser written for (predominantly) HTTP.it was good at that time ,but then other browsers took thae mantle and Nestcape was dethroned. The same may happen to bitcoins. It could be dethroned and for all we know Dogecoin or Litecoin could prevail.
My personal estimation is that it will hover between $1000 to $2500 for the next 24 months at least. I personally see the 5~10 year future of Bitcoin as a series of reactions. The disadvantage of this cryptocurrency is the volatility and threat of future regulation by the government.
What I think we'll see in another couple years is bitcoin as another payment method along side option like credit cards,paypal, pay with amazon,Google Wallet,ACH etc.
In U.S dollar terms , Bitcoin is 11 times more volatile than the British pound and 3 times more voaltile than oil. Anything that volatile is not a reliable payment method or store of value.
According to a member of the European Central Bank ,Bitcoin's future is as a "regional currency".
it could be a long term but its still an imminent threat to nations economy.