Astroturfing defined

I've been out of the PR/lobbying scene for a while so perhaps "astroturfing" is common parlance, but I'd not heard it until I read this blog by Corporate Engagement.

Astroturfing, a play on the phrase grassroots, is defined as in Wikipedia as:

"a form of propaganda... techniques usually consist of a few people discreetly posing as mass numbers of activists advocating a specific cause. Supporters or employees will manipulate the degree of interest through letters to the editor, e-mails, blog posts, crossposts, trackback, etc."

Not a new tactic, just a new name? Every other political campaign includes an element of orchestrated spontineity; it backfired spectacularly on the National Party Research Unit at the live leaders debate out at Avalon last year.