I think theres already a few lesbian characters in the DC Universe.
I follow the Batman range of comics but not heard much about this yet. It's probably a couple of months away still.
They changed the current Batgirl quite a lot. The original Barbara Gordon Batgirl ended up in a wheelchair after being shot by Joker.
The "new-ish" Catwoman is a Lesbian. If its done right I don't think it will change much. Nice to see they are using real circumstances I suppose.
I'll keep my eye open for any news.