So, I was a little put off by the mainpage article about the Swedish using the Bechdel test, and noted that only one of the Harry Potter films passed. I thought that sounded weird, and because I have nothing better to do/cold meds make me an obsessive kind of weird, went through the archives on http://bechdeltest.com/ and found that the original article is wrong! I posted this in the comments section, but since I'm grey on the mp, figured I'd share this here too since it seem interesting.
Sorcerer/Philosopher's Stone: Hermione and McGonagall Discuss the troll
Chamber of Secrets: Hermione asks McGonagall about the Chamber, Ginny asks her mum where her jumper is, McGonagall and Pomfrey discuss who was taken into the chamber
Prisoner of Azkaban: Hermione and Trelawney argue about transfiguration
Goblet of Fire: First fail. There is whispering between female characters, but never shown dialogue.
Order of the Phoenix: McGonagall, Trelawny and Umbridge all speak to each other about teaching at various points.
Half-Blood Prince: Good deal of discussion on whether the Bellatrix/Narcissa convo counts, since it's partially about Draco. Still passes since Ginny and Luna talk about the Quibbler/wrackspurts briefly. Also a note of a quick word between Molly and Tonks
Deathly Hallows Pt 1: Umbridge accuses the Witch of stealing her wand, Bellatrix and Hermione exchange dialogue while she tortures her
Deathly Hallows Pt 2: This one is listed as failing, but is the most contentious. Lily and Petunia's dialogue in the flashback, which is very brief, doesn't count as Petunia isn't named. And while plenty of the women speak during the battle, sometimes to each other, there is never any clear cut dialogue specifically.
And I'm out!