Michael Bender, one of the people behind this, gave an excellent invited talk on B^epsilon trees and the possibilities that write-optimised data structures introduce (especially in data base systems) at IPDPS this year. Unfortunately it wasn’t recorded as far as I’m aware, but the slides are available at http://ipdps.org/ipdps2018/bender-ipdps2018-wods.pdf. A more formal introduction to B^epsilon trees is http://supertech.csail.mit.edu/papers/BenderFaJa15.pdf