Twilight Sparkle didn't say her first line until about 7 minutes into the episode.
Fluttershy slowly turns into Flutterbat after the bats were be able to stop eating apples to affect her. She is similar to Seth Brundle from The Fly (1986), directed by David Cronenberg.
Pinkie Pie's hat constructed out of apples is clearly inspired by Carmen Miranda's legendary headgear.
Friendship Report: Applejack learned the quickest solution is sometimes not the best one, while Fluttershy learned not to be afraid to say no and to accept it if she's the one being told that.