Cant mine Blackcoin anymore, its POS currently.
He's saying that imagine if the coin was in its infancy, and you were mining with a Antminer U3 at 63gh/s (Which it probably won't even get close to, Bitmain didn't do so well with that miner), and how much you'd earn.
I'm not too sure, but supposing that the difficulty was at 1 you'd get quite a lot of Blackcoin. Unfortunately it's POS now, so it's unmineable.