I've officially decided that I predict the song will be along the lines of electro-R&B/pop. The whole thought of "Diamonds" being a bit like What's My Name and We Found Love's love-child makes a lot of sense, honestly.
It's slow hippy dubstep, but instead of using heavy bass dubstep they use electro dubstep kinda like Good Feeling's breakdown. It is slow pace like a ballad but with signature Benny Blanco electro beats. It has a very airy and chill vibe, almost euphoric without it being trance. Rihanna sings with her Barbarian accent like WMN on the verses and sings those high notes on the euphoric chorus. the song changes after the breakdown and speed up like Ima Bee.
I can't believe a whole new era is starting in some hours! I just hope all the singles get proper treatment and amazing music videos, Rihanna is ready to slay lifes across the globe once again.