Who believes bitcoin dominance will fall to 20% in 2018?
How do you measure "dominance"? What does "fall to 20%" represent? Fall to 20% of what?
With the strong rise of Ripple Ethereum Cardano Iota and more will it change the playing field?
Ripple and Ethereum don't have the same use cases as Bitcoin.
Bitcoin started as a retail monetary currency, which is now being used more as an investment asset.
Ethereum isn't a monetary currency at all, it's a currency of processing power across the Ethereum blockchain.
And Ripple is a currency for banks to facilitate financial transactions...it's not in use as a retail currency.
You can't compare an apple to a donut to a car and expect your comparison to make sense!
Now, if you want to compare Bitcoin to competitors you need to talk about Bitcoin Cash or Litecoin.
You forgot HashGraph that is a type of super highway being developed for crypto-money
How novel...sounds like every other cryptocurrency I've ever heard of.