So what you are trying to say is that Coinbase and GDAX are going to add 20 more coins to their portfolio?
If its true, then I see a huge uprising of the market once again as coinbase is a to go site when it comes to Bitcoins and other altcoins like Ethereum. There have been rumours about Ripple being added to coinbase and if the information you provided us with is gonna be true, then I think some of these currencies are going to hit coinbase : OMG, QTUM, NEO, NEBL, STEEM. These are just my picks, I hope these gets added.
P.S. Hope this crypto bloodbath will be over soon.