Shacker is the name given to members of Shacknews. More specifically, it refers to those members who post in the comments (especially latest chatty), or post on the articles of Shacknews.com.
Lurkers, while possibly members of Shacknews, are not generally considered Shackers until they make a post. Most front pagers probably do not consider themselves "Shackers".
Shackers are made of all sorts of people from all sorts of places.
Notable lists include:
See also: All Shacker Lists
Communities outside Shacknews