I've been through several different MMO communities and have come to the conclusion that all MMO communities go through the same six stages of community development. It's not always a direct path and sometimes things aren't so clear, but I think the stages below cover pretty much every MMO community I've ever seen.
Stage 1: Birth!
The new MMO is announced! Nothing is actually finalised, but all the promises sound great! New people flock into the forums (mostly to try to guarantee an early beta slot and / or post 'FIRST!' messages) and the excitement is palpable! Why, this MMO will be the next big thing! Lots of people join and immediately start boosting their post counts.
During this stage, your community will act like giddy schoolgirls, tittering and giggling to themselves and gasping with excitement as new information comes out. Lots of suggestions about what the game needs should have will be posted by players who may or may not know better.
The most common question at this stage is "will this game have <feature X>?" written by people who desparately want <feature X> in the game, regardless of whether it would fit or not.
Stage 2: Boredom!
It's been a while since the MMO was announced and the community is frankly bored. Perhaps the MMO hasn't released enough information recently, or the weekly dev profile no longer holds its shine, or the Questions of the Week get chewed up and spat out in seconds, but people are really just hanging around, waiting for something to happen.
Forum activity drops during the boredom stage as some people go away to find something more exciting. Those who remain often end up rehashing the same questions / issues (e.g. how awesome it would be for this MMO to have full PvP / oh no it wouldn't / oh yes it would carebear), creating spam threads or derailing other threads to turn them into spam threads, generally just to increase post count. People will still make suggestions, but they are probably just repeating what's come before. The forum warriors have established the battle lines by now and and whip up a forum war in a mere 3 posts... which is fine, because it 1) gives them something to do and 2) ups their post count.
During this stage, your community (the ones who stick around, anyway) will act like a group of travellers stuck in an airport lounge while their plane is delayed indefinitely. The same conversations get repeated. Awkward silences are common. Everyone gets antsy.
The most common question during this phase is "when is beta starting?".
Stage 3: Resentment!
Closed beta is announced! Long-time community members refresh their inboxes once every fifteen minutes to check if they've got an invite, then spend the next 14 minutes going through their spam filters just in case! Players who get into the beta get to have a secret and can be all silently smug about it, while those who didn't really wished they'd spent more time upping their post count. New players join the forums, in case they get lucky enough to snag an invite while exited members return to post a few new replies to show that they really were part of the community all the time.
Forum activity goes up during this time, driven by the desire to know more about what's going on in closed beta and by a desire to do more than read about it. Private messages fly everywhere, asking, "Did you get in?". Long-time posters are scrutinised to see if they drop off from posting. Everyone suspects that they are the only one not in beta and that everyone else is having a great time. The tension builds.
During this stage, the community (swollen with hangers-on who just want to get into closed beta) will act like a group of travellers stuck in an airport lounge while their plane is delayed indefinitely, except that they've been forced to wear blindfolds. Everyone knows that some other people have been let onto the plane, but most of them are still waiting. The strength of this resentment is equal to the length of time in Stage 2 multiplied by the number of forum warriors currently not in beta.
The most common question during this stage is a tie between "how do I get into closed beta?" and "when is the open beta starting?".
Boy, this got long! I've split it to break the wall of text - Part 2 is here.