Punchline and she has a decent character design, but that's about all we know.
I do not know if she'll be an interesting character as nothing has actually been released with her yet, people are just getting hyped and DC is eager to make her a new hot character too with her popping-up in many books after the cameo. The first full appearance will be within the pages of, "Year of the Villain: Hell Arisen," #3, and then she will feature in the 90th Batman issue and I imagine other books. Also, she'll be on the cover of, "Batman," #94, which is pictured above, and that might be her first cover appearance if I understand things correctly. We shall see if the excitement for Punchline is warranted or this ends up being a big false start. For now, my suggestion is to try and get a copy of, "Batman," #89 for cover price if you can because otherwise, you may have to drop $35-$40 to see what all the fuss is about.