Bitcoin has grown exponentially in its value and adoption. The community effect and innovation is indispensable but underlying all of it is the genius idea of the block chain incorporated into a payment system, and indeed as a whole economic system. P2P currencies are an economic revolution, their overall future impact is still murky but it will be significant in my opinion.
The Bitcoin currency has, of late, been subject to ridiculous speculation and multi-millionaires throwing money around, creating an unstable market. As the hype of crypto-currency eventually subsides, the price of Bitcoin will become far less volatile. In the future, Bitcoin will be used for speedy transactions that will be less open to fraud and other illegal things.
For the foreseeable future, Bitcoin will remain a viable currency that's worth investing in. The price has risen from pennies on the dollar to hundreds of dollars. Many governments are showing a willingness to allow Bitcoin to become a more legitimate currency. Therefore, its future looks fairly bright right now.
I think that Bitcoin has every opportunity to remain viable in the future. It is true that it is a volatile currency and that the market is volatile just like stocks, but there is no sign as of yet that it is in danger of losing it's value without gaining it back.
No, Bitcoin will not remain a viable currency in the future, because people will move on to something else. Where there is money to be made, there will be another competitor who wants to move in. They will undercut, and that new currency will take over the market. Also, the government will take steps to shut Bitcoin and other currencies down because they compete with the U.S. dollar.
I think that Bitcoin will not remain a viable currency in the future. I think it's popularity and it's value will fade over time. Right now there is a lot of hype over it. Eventually it will fade. Because it is not a physical thing, that might make it harder to keep a high value in the future.
There could be times when crypto currencies and electronic decentralized currencies are very viable, but Bitcoin today is clearly a fad - it will not survive very far in the future and is purely of speculative interest today. While I wish for Bitcoin's success, I still do not believe it will be long lived.