People will unconsciously emulate those they perceive to be of higher status than themselves: for example, people's accents tend to change to sound like those of the highest-status person in the room. Similarly, people in the online community will behave like those who have good reputations in the community. If the people who have high status are committed to the community, others will be as well.
Status is also as a way of advertising one's behavior to other users. People can see whether a given user is socially important and a major contributor, or whether they are a perpetual troublemaker. The public quality of status acts as a check on user behavior, since most people would not like to have bad behavior made public. It also is an inherent reward for those who behave well, since everyone will be able to see their new social standing. But beyond the effect this advertisement has on the user's behavior itself, having public status also helps others make intelligent decisions about who they want to be involved with in telling a story. Users who are similar in their goals and behaviors will cluster together, creating a more satisfying experience for all involved.
A third way to make status meaningful is to assign concrete privileges and roles to users with high status. Status as referent-less hierarchy marker and status as advertising are both useful, but there has to be some way to decide who has the concrete power in the narrative system. There are certainly roles that have to be filled, such as arbitrators to settle in-story disputes, administrators to handle the running of the computerized aspects, and moderators to make certain that the forums remain a topical and pleasant place to gather. Each of those roles also has concrete privileges associated with it, such as, for example, the ability to add and remove users and posts. If these become rewards for high status, high status becomes desirable not only as an end in itself, and not only as a way to attract others, but for the special privileges it can confer.
