[CydeWeys]

Editing a wiki is the kind of experience that is much more valuable to employers than social networking or most common online activities for most occupations, with the exception of marketing/PR-specific roles. Collaborative work on a wiki involves teamwork, research, editing, effective communication, and a whole host of other skills that are useful in a business setting. Blabbing to your friends on Facebook or Twitter doesn't develop these skills.

[Toast_]

My first thought if I was hiring, and a prospect noted that they were experienced in editing wikis, is that they were involved in blackhat SEO.

[jldugger]

Plus, people who edit Wikipedia are less likely to put too much faith in it when doing research.