Hi yub,
I rather like body writing, I havent done anything permanent along the lines of tattoos or branding (I enjoy unmarred skin too much... thats not to say it remains that way, but I use 3 things for this sort of play;
1) Crayola kiddie pens: these last until the next time you sweat heavily or shower
2) permanent markers: 1-3 days duration depending on showering and other factors, but sometimes come off on certain plastics, can be removed at short notice with oil and a good scrub.
3) henna paste, 3-5 days, this stains the skin red brown, and again the duration can be flexed by showering and amount of time in the sun and stuff like that.
the commonness of the use of body writing depends on the Dom, and if its their taste or not.
the photos in the link you posted look like they were done with permanent marker, and that was possible slightly enhanced in a photoshop style program or written over multiple times.
hope that helps a bit
U.