MLPF has about 13,000 members according to the thing at the bottom, yet the member list shows only about 12,660. This is because the front page counter counts banned members, while the member list does not.

Of these ~12,660 members, about 7,100 have 5 or less posts, and about 3,860 of those have 0 posts. Of the 0 post members, about 1,140 have avatars, meaning that they cared a little about their account, at least at the beginning.

There have been about 4280 reports. I think. I haven't been a mod since the beginning, so I don't know about any changes that could have happened that would change this.

Highest post count is (still) aka Crona the Critic aka FinestHour aka tons of other names. He has 8,313 posts, not counting thousands more in RPW and Cloudsdale. If you took all members with 5 or less posts and about half of those with 6 posts and combined them all, he would still have more posts. He is also still the only member with more posts than the Mailmare (the bot who used to post threads in the bulletin section).

Approximately 2680 members opt in to ads.

@~Chaotic Discord~ has the most profile views. He has over twice as many as the member with the second highest number of profile views (@Jonke).

Out of the members who have listed a favorite section,Welcoming Plaza has by far the most members listing it as their favorite section, with about 880 members.

Feedback and Suggestions is tied with Equestria Girls for the least, with only 4 members listing each as their favorite

@Vinyl Scratch was the first non-staff member to join the site. About 140 people joined on day 1.

Approximate numbers of members who list each pony as their favorite:

No preference - 400

Twilight Sparkle (i.e. the correct answer) - 200

Rainbow Dash - 380

Pinkie Pie - 200

Applejack - 140

Rarity - 160

Fluttershy - 300

Approximate numbers of members who list each pony type as their favorite:

No preference - 480

Earth - 160

Pegasus - 580

Unicorn - 300

Alicorn - 180

Crystal - 60

The number 1 shows up in the most usernames (about 800). 8 shows up the least (about 280).

The curious and mathematically inclined might notice that the vast majority of the numbers I listed are multiples of 20. This is because the member list defaults to displaying 20 members per page, and pages are easier to count than individual members.

Anything else anybody wants to know? I had fun doing this.