Date: June 18, 2016
Route: LAX-JFK
Fare: X ("W" Comfort+)
Status: FB Gold
What happened: Error in the seat chart led to people being assigned non-existant seats, after about 20 had boarded they requested those who had boarded exit the plane to have their boarding passes rescanned and seats reassigned. Led to a 25 minute departure delay which resulted in an arrival 5 minutes late.
Compensation: 15,000 miles to my FB account, other DL medallions on the flight received 10,000 SkyMiles, unsure if applied to all passengers or only those who had to reboard. 1 free alcoholic beverage for economy as well. Also email apology that seemed to have been written specifically for the flight.

Thought I'd also add that I didn't complain, I had already received the apology email which promised the mileage compensation when I checked my phone after landing. Considering it was only a 5 minute delay in the end, I thought it was a bit generous, but of course I'm not complaining.