I guess I know which pub you mean. I know almost all 63... But I only wanted to share those who announced it publicly. Mediums goal is to increase the number of pubs on Medium with the Boost. The Boost supports editors and publications because they have more power. I think that's important to keep in mind.
Remember the Summer of Writing or the bonuses? Dunno where this money came from but I bet Medium could pay writers more but since it's a content mill they don't. So they pay some writers more and Boost them because they deliver on Medium's promise: high quality stories from experts.
Great questions though. I'll forward them to Ariel. Maybe she can answer some of them.
By September, Medium will have 100 Boosters. Let's wait and see how it will evolve from there.
Have you registered for Medium Day already? I did this morning and am excited to join the fun.
P.S. people forget that they can also get Boosted if someone sees their stories in a (not-Boosted) publication or on their profile page.
There's one Nominator who Boosted a story that was in a publication without a Nominator. There are also several writers who constantly self publish and get Boosted a lot.