I can think of 8 or 9 authors that make it a point for their characters to talk fondly, nostalgically, and specifically about Buffy. ("Naomi & Ely's No-Kiss List" by David Levithan and Rachel Cohn even has a mix-tape section that covers your average super-fan's disillusionment during the 6th Season; and "If I Stay" by Gayle Forman does a great job of evoking both the elation and despair of watching the show in general.)
Which came first? Were already-established writers attracted to BtVS because it shared their sense of humor and a specific type of emotional resonance, or did the show itself provide them with the desire to write, and the inspiration and confidence to pursue a career in it? Were the characters and stories of the Buffyverse so beloved and so ingrained in their DVD-box-set-owning hearts that they thought, "I can do this, too"? Because they could. And they did. And they're awesome.
Here is my geek cred: I wrote a good ol' fashioned snail mail letter to Buffy and Battlestar writer/executive producer Jane Espenson about nine years ago, asking for writing and career advice. Not only did she write back, but I still have her letter inside a plastic cover. And now I have a couple novels written and a superheroine lit agent. So thanks, Jane!!