What is it that they do exactly when they speak of fender rolling? I know it's to prevent the tires from rubbing against the wheel wells, but are there any pics of what exactly is involved?

hope this may help:
http://integra.vtec.net/wheels/rollfender.html

Wow that doesn't look too nice. Bending the body like that... is it permanent?

or u can see how professional does it:
http://www.robsaudiworld.com/fender.htm

yes it's forever until u change ur fender...