Is It Viral or WOM? What's the Difference?

I've been having a really interesting Twitter debate (Twitdebate?) with Christopher S. Penn and Albert Maruggi about the difference between word of mouth (WOM) and viral marketing. You can follow Chris and Albert on Twitter as well.

Albert was wondering what to call the spread of a commercial like Swear Jar and Chris chimed in with "word of mouth." I disagreed, saying there's an inherent difference between WOM and viral. I would have elaborated, but you know, 140 characters and all...



So I'm opening it up here to a larger debate. I think that WOM is a one-to-one or one-to-few methodology with an influencer asking for the listener to try / look at something. The expectation is that the listener will then start using a product or service. There's a specific call to action.

Viral, on the other hand, is much more about creating something that is dependent upon network of people to pass it along. It's a one-to-few-to-few-to-few.... model. If a campaign / site / video goes viral, it does so by virtue of being worthy of being passed along and without a specific call to action (albeit the unspoken CTA is "pass this along").

I guess I'd sum up my position as follows: WOM is tied to making people try/buy things and if done well, results in a long-term impression. Viral, on the other hand, is tied to making people pass things along and is more or about creating a quick buzz.

My Parthian shot: people create viral videos, not WOM videos.

For more information, the Internet Marketing Driver had a great post on this subject.
Update: here's a post from Seth Godin that stuck with me and influenced my position above.

So now the fun begins. What do you have to say about all of this?