You could call it stencil-style, or screen-print-style, or stamped, or posterized. The purest form of this type of design has two colours (usually black and white) with no halftones; a given point is either full black or full white. It is tailor-made for screen-printing, either white ink on a black(ish) shirt or black ink on a white(ish) shirt.
I enjoy applying this technique to political figures, mainly American ones because, let's face it, that's where the fireworks are. Where possible, I use source photos that are Public Domain or at least have a license that allows commercial use and modification (CC BY, in the Creative Commons), and generally donate the results back to the Commons as Public Domain. We live in an Attention Deficit culture littered with memes, symbols and icons, and it's my belief that these highly graphic portraits can find some use in that mix as a kind of iconography.
Because filling the white portions of these images with a full colour photo doesn't prevent reverting them to black and white easily, I started to do so. It made them more complex, more appealing, and I could comment on the subject with my choice of filled texture.