Is Excoin and NightTrader both BC focused exchanges? 
What is the point in a BC pairing if noone use it! Look at Bittrex
Noone use BC markets! why?
What is the point in a BC pairing if noone use it! Look at Bittrex
Noone use BC markets! why?
It doesn't matter, Excoin, Night Trader, and the other unannounced exchanged will all be used for their own distinctive services and what they offer.