I believe that fandom also has a social element. This is why Ayn Rand had no real fan clubs, just individualized Randroids.

No. :)

Seriously, I just don't see it as qualitatively distinct from other strong interests people have. I'm inclined to think that the only reason anyone does, is because of a kind of snobbery against it. As you say, we don't call people who are extremely interested in, say, Shakespeare and continually immerse themselves in everything to do with Shakespeare, "fans" who are part of the Shakespeare "fandom".

There's a reinforcing cycle in the things that people have the strong and most-abiding interests in. Their interest influences both their social and self identities, which just invests them in the topic even more.

As to why some people go deeper into certain things and do so for longer periods of times than others, well, isn't that normal human variation? I'm an extremely curious person. I'm very much a novelty seeker, but it's directed mostly to intellectual stuff (and artistic stuff). So I generally don't get as deeply into something, nor for as long, as many other people. But, on the other hand, I'm usually more deeply into a wider variety of things than other people are within the context of that many different things.

Fan fiction...I dunno. I have precisely zero experience with it. The only fan fiction I've ever read is stuff that's not called fan fiction because it's professional fiction that's derivative, such as (mefi's own) John Scalzi's "Fuzzy Nation", which I read yesterday. But I have thought about why people want to write such stuff. There's a few characters here and there that I'm both interested enough in and fond enough of, that the idea of creating new stories for them is attractive. It's nothing I've ever done because, well, some of the reasons you'd probably expect.

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I believe that fandom also has a social element.

Yeah, very much so. It's a social identity thing, and social interaction of some form is integral. And maybe that's why "fandom" is more visible these days, because the Internet greatly facilitates the ability to be fans of something in the social sphere.

There was a thing I read a few years ago that I fell into enough that I went looking for fan fiction and other derivative works after I had finished the main thing. I was a bit obsessive about it for a while. Fortunately, there was very little fan/alternative stuff in existence, so the fire died after a while. It wasn't a social thing at all. I'd just fallen in love with the characters and just wanted to read more about them.

I'm basically with kmellis, sports fans have their fantasy leagues and whatnot, some people use enthusiast or geek or whatever. I think the biggest difference with fan fiction is that it's more typically women, writers and sometimes a certain age range, but that varies as well.
I think the closest comparison I can think of are people who get really into comic books and want to use those characters in their own stories. There is this thing about talking a work apart and playing with its elements, usually the characters, instead of the thing as a whole, and the comfort and escape of his other world to inhabit. It's not necessarily social, you can consume a lot of it without any interaction, and I gather some quality work comes out of it.
I always found the odd bit to be using other people's characters instead of making your own, but it is any easy way to get people to read it. Some people want the interaction and community, some people just want the stuff, sometimes something just clicks at a certain point in time.

The only people I personally know who have been heavily into fanfic are writers extending their enthusiasm for something. One is very escapist, and depending on your interest, there is a lot of information to be had, so you can hide there for a long while.
People do seem to have more of a sense of humor about it than, say, a history buff. I know someone who was talking derisively about ren faire folk until I mentioned that they could be just as into anything, like crafting. As she's a compulsive knitter (I did not know this at the time), she changed her tune.

I don't know why people need to validate things so much. I wish I was really into mysteries or romance novels because there are tons of them, or really into sports or video games and had this reliable thing at hand at all times that always worked. I feel grateful when I find something I can really enjoy for however long it lasts, and a lot of that is being in the right mood for it or conditioning.

I suppose you could say it's a problem if it's not a functional coping strategy, if it's interfering with your life, or you find it distressing. That's not really about the thing so much as your relationship with the thing.
When an interest becomes a "lifestyle choice"-- well, I guess it depends on how much of a conscious choice you are making.

I just don't see it as qualitatively distinct from other strong interests people have. I'm inclined to think that the only reason anyone does, is because of a kind of snobbery against it.

Thoroughly agree.

I believe that fandom also has a social element.

And this might be the two-sided coin that in part explains why 'fandom' sometimes gets a bad name - because while fandom unites, it also separates. We've probably all known someone whose powerful interest in something seemed to grip them for a time, or forever, and if you didn't want to talk with them about that topic, couldn't relate, found whatever they liked boring or stupid...well, that can create some distance. It can wear people out if they're not right there with you.

And usually, people are pretty good at containing their fandom and only really letting loose the full expression of their geekiness on a topic around others who share the interest - but sometimes they are not. And perhaps for people who are less able to read social cues, this becomes a more obvious and serious problem - they may not as able to confine their expressions of fandom to contexts where it's welcome, or at least unremarkable. THis can give rise to expressions which others (who don't share that kind of fandom) respond to by branding it with social stigma.

Based on watching a friend be immersed in the Harry Potter fandom, then Harry/Snape slash subfandom and then the Tim Minchin fandom (she always seems to find a new one when she loses interest in the current one), I would say DRAMA! is a big part of of the fan sites. A lot of one upping, behind the back gossip, perceived back stabbing and what not. So in that way, the social part of it can be quite unhealthy.

My only experience in fan fiction was Labyrinth in college. I had to find something to use the shiny new internet for :o) And it was very much like DarkForest described except there was a good bit of stuff out there. Nothing else has interested me enough to seek out fan fiction like that though the Crowley/Aziraphale slash is awfully tempting.

That's interesting about DRAMA. Would you say it was about participating in it or watching it, or would you say that watching it is participating in it?
Is this a facet in other parts of this person's life or confined to the fandom?

For the most part, she's drama-free and can't stand it any more than I can. So my knowledge of the fandom DRAMA is limited to her mentioning it in passing (e.g., she had disengaged from the Tim Minchin site and yet someone was still trying to pull her into the current DRAMA). From someone with no direct personal experience, it feels like the same crap you'd find on various livejournal sites.

The thing about fandom that seems slightly separate from other enthusiams is that people in fan circles that I have known have the fan stuff as the overarching uniting theme and act like because you like $_THING then you should all go to the same parties, particpate in the same activities, etc. Like sports enthusiasts are a big enough bunch that you can find your *own* type of sports fans, but if you're into a pretty specific subgenre of fandom you may not have as many choices, so you're tossed together with a bunch of people who might or might not share other personality and social traits with you. Hence: drama. This is mostly my outside looking in take based on being a library person who intersects with fandom people from time to time. See also: internet people.

So drama in the inflated, somewhat manufactured sense and not the minimizing actual conflict sense? Is this for people seeking the community aspects, going group to group? Like people who get a lot of personal identity from group identity?
At what point is someone a "fan"? Self identifying? Group identifying?

I was in Star Trek and Sci Fi fandom for most of the 1970s and 1980s. That kind of fandom was all inclusive and all about accepting anyone. PM me for more info. Too tired to talk.