There's a regular NANOG talk called "Everything You Ever Wanted to Know about optical" available on Youtube (multiple versions/years) if anyone wants to get into the weeds.
UKNOF also had some recent talks on >100Gb/s stuff:
* https://www.youtube.com/watch?v=TQIPT6e2uRA
* https://www.youtube.com/watch?v=ActDnpR4ENY