This is the first time in the series a two part episode had the same name for each part.

Batgirl finally settles with the name Batgirl.

Alfred: The Dark Knight has a green thumb?
Batman: This leave-behind is my only lead, Alfred. And so far, it's definitely not garden variety.

Batman: Let me make myself clear: there’s no room for a Batgirl in Gotham.
Batgirl: That’s cool because it's Batwoman -- as in, I'm a grown woman and don't need to listen to you.
Batman: Then for your own safety, if you won't listen to me, I’m going to have to tell your father, Miss Gordon.
Batgirl: Uh, you must have me confused with someone else. (Batman glares at her) Dude! You just broke the superhero secret identity code!

Batman: (to Batgirl) Not every child gets the opportunity to rescue their parent. I'm sure he'd be grateful if you decided to tell him.

We don't really know how Batgirl made the batarangs she uses.