First of all, I'll just say that I enjoy this episode much more than the pilot, and I think it was a fine choice for them to play it afterwards on premiere night. Although the pilot is great, this episode really fills out what to expect in the series.
"The Harvest" features its first run-in on public displays of vampires. The Bronze ends up being infested with them, and many Sunnydale teens are bit and killed in the process. Now this is some pretty exciting stuff for only being the second episode. However, everything is "back to normal" in the end because we come to find out that the residents of Sunnydale seem to have this weird selective memory disorder... It's not really mentioned, but it's there. Sometimes this bothers me, especially at the beginning, but as the series progresses, the writers find more better ways in hiding the fact that demons exist, and you tend to get used to everyone's selective memory. The only ones who seem to remember are the Scoobies (the name of the core group).
I also have to say that this episode shows more of Xander and Willow, and it made me realize how much those two really hold the show together. Buffy is great, and so is her uptight Watcher Giles, but seeing Xander and Willow interact with one another is something to enjoy watching. Even just the conversation they had in the hallway about how Buffy will be fine going after Jesse alone, they create this comforting atmosphere that you can somehow relate to them. They are the outsiders looking in on Buffy's exciting and adventurous life, just like us. (Although Willow mostly gets more into it later on.)
It was also very clever of the creator Joss Whedon to have this character Jesse, who people would assume to be a recurring character, end up becoming a dusted vamp by the end of its second episode. It's just another one of those twists that people won't expect, such as the opening of the pilot. It also introduces Xander's hate for all vampires, which becomes a major aspect of his character throughout the series as well.
I do really like this episode, even more than the pilot. I especially love the ending because, although its corny, Giles lets the Scoobies (as well as the audience) know that it won't just be vampires Buffy and the gang will be fighting. Which we soon learn in the next episode.
"The earth is doomed." - Rupert Giles