Guild Wars 2

So, how do you find these vendors in the maps? I know they travel, but do they have special icons that you can see in map view? I assume you have to be in the zone. I was just WP around to different ones looking at the maps, but not seeing anything out of the ordinary.

Ok, found one in ebonhawke, and it basically looks like the normal icon for a vendor.

Could these guys get a different icon? heck, make it purple to signify karma