That is correct. They start with BTC and ETH. Once successful, I think getting other coins added will be a procedure only. The market cap needs to be big enough and liquid enough for big money to be in it. By this time next year, with the fully functioning options market, a market cap significantly higher than today, I think the cryptocurrency mystery the vast majority of the public don't yet understand will start to bleed into commonplace conversation. Just like back in the mid 90s when websites were so new and most businesses thought giving access to employees was a way to ruin productivity, the applications for the blockchain will start filtering into regular businesses.
My $20K crypto account (my cost) I'm confident will one day be $1M +. It's already $95K since march with one position yesterday up 5500%! I'm only thinking about adding to positions and have absolutely no worry about corrections. I see them as opportunities. You can't stop this train.