I've been reading BoP since the very first one shot back in '96, and with the exception of a lull in the title after Dixon left, it has been an excellent read. Simone, however, turned a good book into a great one. I haven't picked this ish up yet, but I'm looking forward to it.
I also thought that Jim knew about the Batgirl alt id. In Batgirl: Y1 you can tell he suspects and I cannot remember what issue it was in (mebbe one of the Batman Chronicles issues) he talks about how he never told Babs that he found her Batgirl costume - he knew she was BG, he just never told her he knew. The Oracle angle I don't think he knew about though.

Dear, sweet Harley Kwink...I'm madly in love with you. Marry me! We can go to Canadia. Or Boston or something. It'll be grand...You know the cookies are a given. They are ALWAYS a given. You could dump me tomorrow and you'd still get the cookies. Boston..shit, wherever dyke weddings were legalized. And where better to rub their little piggie noses in how bad they suck than right on their doorstep? What are they gonna do? Be jealous of you? Stare furiously at your tah-tahs? Not willingly give you cookies, but instead begrudgingly give you their cookies? Woman, time to wake up to the powers you wield - Uschi