What currency will it use of not Bitcoin?
For me the people to listen to about blockchains are Peter Todd, Gregory Maxwell, Adam Back, Luke-Jr and there might be some names I have forgotten so please post them in here.
i guess your eluding to the hyperledger
blockchain that all the
names you mentioned are programming.
the problem with that is that hyperledger is FIAT
so companies like circle if they drop bitcoin.. will just be a bank holding fiat. making them a forex company swapping america's fiat for lets say india's fiat. rather than an open currency without borders.
the problem is that there would be no need for that because the hyperledger itself can do those fiat swaps directly. thus not needing circle.