Alyson Hannigan was not yet cast in this Pilot. Willow was played by Riff Regan.
Sunnydale High is not yet Sunnydale High. The name of the high school is Berryman High.
While talking to her friends, Harmony mentions a band called Dingoes Ate My Baby will be playing. We later find out that this is the band that the Oz character plays in.
As this was a pilot episode, just meant to give an idea of the show, the runtime is only about 20 minutes.
Don't expect to see the familiar Sunnydale school library in this pilot. As with some of the other settings, this set is not the one that appearances in the show. This one is an open-aired, 2-story layout, from which you'll see Buffy flip off the balcony of.
Vampires don't yet explode into dust when staked. They slowly turned to dust from toe to head (seemingly), then sprinkle to the ground.
Darla (whose name we don't technically know yet) seems to be killed in this episode. Willow holds a cross to her head and we hear bubbling, supposedly from her skin.
The character of Angel does not exist as of this unaired production and is not included in the cast.
Buffy: I don't suppose you'd be sweeties, attack me one at a time?
Buffy: (after being thrown across the room) Oh, ow, that was my favorite spine.
Willow: (after being bitten by a vampire) Oh, Mom was right about boys...
Xander: (to Darla who is about to attack) I don't like to hit girls that... I'm afraid of.