The Word of Mouth Marketing Association has posted a code of ethics on its Web site.

NPR: Slate's Ad Report Card: Burger King's Buzz Marketing

There are other approaches as well such as those described by the Word of Mouth Marketing Association.

FORBES: Can You Measure Your Digital Eminence?

Its been a hotly debated issue for months at the Word of Mouth Marketing Association, the leading trade group for viral marketing.

FORBES: Buzz Patrol

On Wednesday, Nov. 16, I will participate in a panel discussion at the Word-of-Mouth Marketing Association (WOMMA) Summit in Las Vegas to talk about the efficacy of online versus offline word-of-mouth (WOM) marketing campaigns.

FORBES: Why Digital Still Can't Beat Word Of Mouth In Sharing Brand Messages