My impression is that as general currencies only a few will survive. Where it might blur is where the blockchain aspect is getting used over the currency aspect

My impression is that as general currencies only a few will survive. Where it might blur is where the blockchain aspect is getting used over the currency aspect, and there one might think of it more as apps or exchanges of 'currency' or work tailored for specific markets. Still, I'm pretty skeptical as I think so far all the uses are more hype-supported than providing wide scale value, but that's balanced by a lot of people exploring a lot of possibilities.