Guess I'll try to go in order:
Biggest Covenants:In terms of general covs everyone is in, I guess it's easy to that say it's either the Darkwraiths or the Sunbros. One if you're pvping, one if you're cooping. Others get used as well such as the gravelords, Forest Hunters and occasionally the darkmoons, but they're not anywhere near as popular.
Influential members:There are quite a few here. The first people I have to give a shout out to are FexDS, Emergence and Ublug. They have run the forums and our wiki since day 1, and have ensured the forums have the best atmosphere possible. I've been on both sides of the lot of them, and from being around them for over 1 1/2 years I can say we're lucky to have them guiding the way.
From the general members of the forum, there's quite a few. Tolvo who posted above has created hordes of threads that are useful for players both new and old. Members such as Blaine and Retro have tirelessly done research about the game and have really 'mythbusted' a lot of stuff that we really had no idea about for a long time. DxV basically wrote the rule book on gravelording and really helped pave the way for the wider use of the Gravelord covenant. We've had popular youtubers here such as Rosie and Jblackmel, but sadly both no longer upload. The final member I'll mention is RANT. He created the first Dark Souls fightclub on this forum. His leading of that basically popularised the concept of fight clubs using hosting duels. Obviously things like that have existed before, but the scale it is now used throughout the online community as a whole and the fact the method is now used for forum events shows how influential it was.
PvP:General PvP isn't policied. Since day one the admins have encouraged all forms of pvp to be looked at in an objective way, and to understand that there are a variety of ways to play the game. However still there are things that the community generally disagrees with such as ganking and healing mid fight.
In terms of other parts of the forum, we have had and continue to run fight clubs, have both forum wide and more grouped events. Those generally have rules, both for roleplay reasons and for to shape the way the fights go. The fightclubs vary from fairly restricted rules to completely anything goes clubs, while the events usually have themes to make them more interesting, and to encourage people to play in a different way or with diifferent weapons than they usually would. Good examples of that are the legit low level event (only use equipment available before a certain point in the game) and the dragon weapon event.
The Roleplay section (User Covenants):Really this is a tough one as it has varied so much. Many covenants run well for months and then fade out because core members stop playing or leave the forum. Off the top of my head there's 3 or 4 large user covs that disappeared due to that.
This really was born from the first user covenants when they were created- Airglow (Now Nightwatch, though really defunct as far as the forum population goes), was the first user covenant, which I helped set up with another former member, StrikBH (who was on the old wiki based forum, and never came back) and the also now defunct Assassins of vinheim. Pretty much the creation of these led people to wanting a section for it. Who suggested it, I don't know.. perhaps someone will come forward. I hope they do anyways

The section is for user covenants- groups of individuals that the leaders and key members create lore and a story for, create a concept for the covenant and usually choose an in game covenant to base it in. Shown by covs such as the darkstalkers (Wraiths) and The Sunlight Coalition (sunbros). However, there are covs which don't specify covenants and which can use anything really like the Exiled of Ariamis.
Right now the cov section is dwindling a tad due to the low number of people still visiting the forum, but the strongest covs are the Darkstalkers and the Exiled of Ariamis. Both very invasion focused. However, while the activity is lacking we still see events (such as the recurring 2v2 guerilla warefare event done by the Exiled), that are held by each of the covenants for everyone to join in. I hope that when the next game comes, the cov section will thrive again, and hopefully at the height of it's popularity that section will be rife with unique ideas and fun events.
The Departed and Why I remain:Really people depart as they tire from the game, however generally they never permanently leave :PThe game and this community is so good and addictive that people can't help but come back. You regularly see people announce that they're 'leaving' in off topic and then a few months later they're back. It's just a regular occurrence and I feel a testament to the community and the game that some on here have event spent in the thousands of hours playing (I can't profess to have done that myself)
Why I remain here? Well, even before I had moderation roles to undertake, even when I didn't play the game I still come here as the community is great. Talking to people about dark souls, debating, taking part in the covenant scene, lore discussion, as well as talk in the off topic sections. The fact is here we are a close knit community. While this is not as evident right now due to the fact that fewer people remain, the fact that people come here even just to talk to others in the community in the off topic section shows how great this place is.
The other fact is, I've probably spent more time on the forum than playing the game, and while with around 700 hours clocked in game that may be a worrying figure, it's a testament to the community.
If you have any more questions you'd like to ask please contact me via PM

Also I'm moving this to the forum discussion section, as this is very much the most literal discussion of the forum I have ever seen
