Different question: What is your story of the year? Could be film, book, something on this forum, anything.
I'll keep it to the M:EM, just because that is this forum.
Unfortunately, it's been a pretty lean year for the M:EM, with both Orcish and Ruwin gone for the vast majority of it, and looking back, not all that much has been written this year in terms of stories. For other people's stories, looking back over the year, the two that stand out most would be Huey's "Dragon's Blood" and Tevish's "Lost Days Record." The first is a nice, simple, self-contained story that benefits from M:EM knowledge but in no way requires it, and features a twist that feels natural but still pleasantly surprising. With Tevish's story, it fills in some long-standing bits of lore that we've known in broad strokes but that hadn't been fully fleshed out yet. Like Huey's, it can stand on its own, but there's a really cool feeling along with it when you are "in on the secret," so to speak.
In terms of my own stories, again, I had a lean year in terms of story production (though I've written more poems this year than any other year of my life). I'm happy with most of what I've written this year, and am fond of several smaller stories, like the game/story "EliseIam," the Space: The Convergence foray "Star Bust," and the M:EM High School story "How Do You Do it?" But I think my favorite story that I've written in 2019 was "Spell Trader." I think the story has a good mix of character- and world-building, and I'm very happy with the overall tone of the story.
Also favorite MEM post or thread of year.
Pretty much my favorite thing around here is the story discussion, and I've always been particularly fond of the way Orcish analyzes stories and reacts to them in general. So if I had to pick a favorite post from the year, the one that stands out the most would be
this one, where Orcish responded to my "How Do You Do It?" story. It's a nice, in-depth look at the relationship between Beryl and Aloise, as well as a look at how facts and details shift in different AUs.
That's the stuff, if I'm being honest, I miss most around here.