They are a fantastic image-board artistic endeavor. I would like to say they are something new, but the general form has been around since the early days, after undergraduates gained access to campus email systems.
Quick drawn minimalistic art is the best. Drawn quests have an advantage over plain text.
Pony quests should be fun, but the few I've tried (elsewhere) to jump in on rapidly dived into what was maximally edgy and obscene. Not that I'm looking for something that could run scene for scene and word for word as an actual televised episode, but damn.