I will start a thread on this (or find the one I made years ago on subject) but as Chuck correctly stated my theory goes like this:
Everyone loves Firefly. Everyone loves every episode of Firefly for different reasons. However, at the end of the day when you ask someone what is their favorite Firefly episode they will fall into one of two camps:
Camp A:
Shindig
Our Mrs. Reynolds
Jaynestown
Trash
Camp B:
Out of Gas
Objects in Space
Both camps will profess their love for all the other episodes but at the end of the day if they had to choose one episode to watch over and over they will fall into one of these two areas.