Hitomi: (to Madoka and Sayaka) I'm off to a popular party. I'm out, nerds.
Ambiguously Bi: Sayaka, it seems. She keeps trying to get into Kyousuke's pants, but loves attention to/from girls as well.
Abomination Accusation Attack: Starting in Episode 2, Madoka begins questioning Mami the details about the whole magical girl schtick. Mami responds by accusing Madoka of smoking, with Sayaka going along with it for whatever reason. Turned Up to Eleven in Episode 3, when Kyubey joins in and Madoka starts being accused of shooting up heroin (among other things).
The Ace: Mami even lampshades it in the second episode.
Mami: Hi, I'm Mami.
(cue Mami using Unlimited Musket Works)
Mami: I'm awesome and I kick ass and I'm probably better than you at everything.
Sayaka: I know, I know, it's your sister's birthday, but I felt that we should celebrate it anyway, because why the hell not.
Kyosuke: But I don't have a sister.
Sayaka: But I saw you walking with a girl before you fucked up your wrist. She was your sister, right? She was your sister. Your sister. Yes?
Comedic Sociopathy: Not surprising given it's an Abridged Series, but one in particular is Mami's nonchalant response to Madoka asking how she can afford a fancy apartment: "I set a rich man on fire." And Madoka accepts this without further explanation.
Curse Cut Short: Anytime "motherfucker" is used as an exclamation of anger or other outburst of emotion. Mami has used it to refer to specific characters, so hers are left alone.
Driving Stick: Mami can (she used to drag race until her Ferrari got totaled). Homura can't (to put it mildly). Kyouko says she can but the scene is over (to her consternation) before she can elaborate.
A Fate Worse Than Death: Madoka and Sayaka are shocked that Mami chooses to save the suicidal woman because she has no Internet access. Life is not worth living without Internet access. Mami tells them to shut up because her parents are dead and she has no Internet access, either. They still seem to see it as a good deed, though the woman disagrees when she wakes up.
Felony Misdemeanor: The suicidal woman in the second episode jumps off a building because she has no Internet access.
Flat "What.": Homura pulls one in the first episode, when she asks Madoka if she values her life and Madoka's response is a casual "Not really."
Genre Savvy: Madoka, when confronted by Kyubey while searching for the creepy man who is promising candy.
Madoka: Oh my God, a stuffed anim—Oh my God, you're the creepy man, aren't you?
Incredibly Lame Pun: When Sayaka and Madoka first discover telepathy, Kyubey calls them "my hos". The thing is, he could also have been saying the word "Mahous" which is part of the Japanese word for "Magical Girl".
All those head-related puns in Episode 3. Mami and Sayaka roll off a bunch of them at the beginning of the episode and pepper more throughout (in Sayaka's case, even after Mami bites it after being bitten). Madoka doesn't understand where they came from all of a sudden.
Meta Girl: Madoka spends the first part of the second episode lampshading Mami's costume and later asks several questions about the nature of magical girls, like "Why is it called a Soul Gem?", "What happens if the Soul Gem isn't shiny anymore?" and "Why do we need Grief Seeds?" Mami's response is to accuse Madoka of smoking/taking drugs.
No More For Us: Sayaka after she and Madoka stumble into Gertrud's labyrinth: "That's it, Madoka. As of right now, we swear off the Doritos - deal?"
Madoka: Why can I never get any comments on deviantART? No one seems to notice my amazing artwork and all its deep complexities. These pictures represent the truth of my whole being, and a reflection of the universe!
Kyubey (slowly): I think it's because you suck.
Soundtrack Dissonance: After the second episode was taken down due to copyright issues regarding the theme song, the team announced that the opening theme in every episode that gets taken down in the future will be replaced with smooth contemporary jazz. Since they didn't change the opening's animation at all, it fits about as well as you'd expect.
Kyouko seems to be the same way towards Sayaka in some of the promo videos.
Sayaka towards Kyousuke - he's changed rooms three times because Sayaka keeps showing up and has no idea who she is. Also, she observes him through binoculars from the casino across from the hospital.
Take That, Audience!: After the end of Episode 3 proper, Madoka (who is voiced by the main driver of the whole project Chiikaboom) comes out and tries to explain why each episode has taken so long to come out, only to be driven to tears by impatient fans and their complaints. Kyouko then bursts in and delivers a major tongue-lashing at said fans, noting the amount of time and effort needed on Director Chi's part for something that earns no money.