Andy Sernovitz who is WOMMA’s CEO, does a pretty good job here of explaining Word of Mouth.

He lists the 5 steps as

1. Talkers
Volunteers, customers, bloggers
Influencer, agent, evangelism programs
2. Topic
Special offer, great service, new product
Viral campaign, buzz stunt, new feature
3. Tools
Tell-A-Friend form, forwardable email, coupon
Message board, online communities, blogs
4. Take Part
Join blog & message board conversation
Outreach teams, campaigns by PR and customer service
5. Track
Blogpulse, Feedster, Technorati, Google
Advanced metrics program, trend analysis