When I worked for an SEO company, we often found ourselves telling clients that we were like the cobbler's children who had no shoes of their own. So busy working for others, we had no time to promote ourselves. Also, SEO is inherently an extremely competitive industry to try and rank for.
Though I still wake up happy each morning that I no longer do SEO, I watch the industry from a distance and was interested to see that Submitawebsite.com has chosen to use paid links to promote their own site. This very post is a sponsored post, and I'm supposed to link to them with the following text:
Of course, the best links are contextual, everyone says -- meaning they should be used in a sentence, like you learned in Elementary school:
Websites sell more product when they rank better in search engines as a result of link building.
Nobody really knows whether Google actually can (or does) look at the immediate surrounding text, or if it's just a function of what other text is in the document. And the result is vulnerable to gaming either way -- you can just use a machine-generated page with thesaurus entries surrounding your target phrase, maybe mingled in with garbled phrases culled from the Guttenberg project.
But actually getting humans to write all your content can be cost-effective and actually-effective, through sponsored links.
But I'm still glad I don't do it from the agency side anymore. Now, picking up a few extra bucks to help me on the path to my Wii... That's a different story altogether!