Name the wager and I will bet you they have him or her come out of the closet with a last page splash of a kiss or some glee worthy monologue or worst have him or her make everything into a sexual innuendo like Marvel did with X-Statix.
I think it is too soon to know what they will do. For all we know right now, it may play out organically, as it did with Apollo & Midnighter. We won't know until the comics are made.
Maturity and Grace?!? Okay now you are just being a DC apologist fanboy. The characters identity is so tied up with being "DC's Lesbian" that they cant have a single issue without working it into the story. If I remember correctly it was even worked onto every comics title page. And there was always some voyeuristic shot through a window of her naked in bed or a shot through an open door of her pinning some woman against a dumpster in an alley. It was about as mature and graceful as "Dolemite".
I would be willing to wager that it will be handled with at least the maturity and relative grace that the Batwoman series has. I don't see any reason why they would take a step backward to your low expectations at this point.