I have no doubts that it doesn't matter whether your favorite show is TNG, DS9, VOY or ENT - some like TOS and some doesn't like it and that applies to all shows. An Enterprise fan might consider TOS his second favorite and another might consider TNG or DS9 his second favorite. It's bound to exist divergences among the fans considering how disparate the shows are and they might like different things in different shows.
However, one inquisition that I'm interested in and that I do not think that has been tried yet on the web is if there is any pattern among those of us who have always held TOS as our absolute favorite. While I have not discerned any common denominators among those who hold TOS as their second or third favorite, maybe there can be among those of us who venerates it the most?
Let the discussions begin!
PS. And remember that if you want to vote, there must be no doubt that TOS is your favorite. While the option "They are all great!" exists, it adheres to that you like all the other shows equally as second favorites.