Poll results for user acquisition: Viral, SEO, word-of-mouth, or other?

Recent poll
I recently had a poll on user acquisition and where people are putting their efforts. To summarize, most everyone put their focus on word-of-mouth and blogs, whereas less folks were looking at SEO/SEM/email/etc to drive their traffic.

Similarly, Facebook/OpenSocial was in a 3-way tie for 2nd place along with the other methods as well.

In general, I'm quite surprised! Here's why:

Scalability of user acquisition methods
One my main considerations, when thinking about user acquisition, has to do with how well that method will scale over time. Ideally it's a "set it and forget it" process (to quote informercial god Ron Popeil), where you can scale to millions of users after solving it once.

In a previous post called Why bloggers and press don't matter for user acquisition, I point out how hard it is to scale the blogs/WOM gravy train, and I've also discussed why tech early adopters are often the wrong folks to target. I think in general I'm pretty surprised people are still going after blogs/WOM when it's pretty obvious to me, at least, that it's not a particularly great way to go.

I could be misinterpreting my own poll option, so let me know if I'm getting that wrong.