In broad strokes, this is Yelp's attempt at transparency, probably the first step in a strategy to realign themselves with quality reviews. A closer look into the reasoning behind this and you start to see the writing on the walls.
This article goes into the specifics, and it was posted almost 3 years ago.
Yelp has always stated they take paid and fake reviews seriously, and now that they are making attempts to rectify their brand image, our best guess is... this is only the beginning.
