Jessamyn is amazing at being empathetic when people have issues with the site, but being firm about the actual decision that have been made, without being patronizing (it's very hard to say "I totally understand your concern, but we're not doing what you want" in a way that doesn't annoy people). And she never ever yells at people unless they totally deserve it, in which case they then realize they deserve it. Unless you are a real malcontent (and of course there are a few), it is really hard not to believe that she is genuinely on your side.

By "issues" above I don't mean technical things like "I can't log in" but disagreements about how the site should be run. Metafilter has a official side site called Metatalk that is largely a forum for people to complain about Metafilter. It is a testament to the Metafilter mods that this actually works.

Especially in some of the more heated discussions, it's very common to see a jessamyn comment like "Removed a few comments. This is a sensitive topic. Please take it to MetaTalk if you need to."

In my opinion, this is one of the major reasons why MeFi is such a pleasant community compared to something like Reddit. Because the mods don't let discussions spiral out into people yelling at each other, and because drama can be dealt with on a separate subsite, it truly feels like a community of mature adults. (For the most part.)

The interesting thing about Reddit, is that in a select few subreddits that are fortunate to have moderators as good as jessamyn, the experience is phenomenal and there is a concentration of domain experts sharing knowledge at a rate and depth to put even Hacker News to shame.

/r/askhistorians is one that comes to mind immediately.