Buying traffic is the easy part. Keeping those eyeballs is where things get dicey. Back in the day, when sock puppets and indecipherable dotcom ads dominated Super Bowl Sunday, we bought traffic the old fashioned way: We got VC investors to pay for it. Much of the first internet bubble was inflated by venture capital hot air. Dumb money flew towards Stanford MBAs with business plans for building a brand out of thin air (well, expensive air time) in the hopes that they could "own" a dotcom category early and monetize it later.

We all know (and will tell our grandchildren about) the fate of the first dotcom model, but the search engine ecosystem of today has introduced a smarter way to buy traffic that is no less perilous for content providers. In the past year, I watched several consumer and B2B content brands ratchet up their traffic by double digits on a monthly basis. When asked, most of these companies admit that they are doing some combination of advanced SEO with actual Search Engine Marketing keyword buying on search engines. A marketing manager at one content site explained to me that they have it down to a fairly precise science of reselling Google traffic for a profit. This branded site knows exactly how much they make off of ad sales per page served, and so they buy keywords on the Yahoo!/Google/MSN triumvirate at a lower cost per click. Every eyeball they pay for via search produces a handsome margin.

Neat little cash machine they got going there, right? Well, until keywords in their category start rising, or their own ad business goes soft. The problem with buying traffic from search is that unless you have a strategy for converting those new users into brand loyalists, you will find yourself repurchasing that eyeball again and again. Maybe that is good enough for ecommerce, but it seems to me a disastrous strategy for content. My marketing manager friend bemoans the fact that as soon as they decrease their keyword buys, traffic plummets. I see this again and again in the monthly traffic reports of the same sites that spiked their traffic through search strategies last year. As soon as they pull back on the SEM spend, they lose that impressive traffic flow. They are cleverly leveraging search on the front end, but the companies may outsmart themselves on the back end. They aren't clever enough to convert that audience so they don't have to buy the same eyeballs two and three times.

Now to be sure, the smart SEM strategy always combines with good SEO. You learn from the successful keywords you buy in order to optimize the page and get those same results free from organic search the next time. But that strategy, while less costly, still keeps a site addicted to the new opiate of content, search.

One obvious strategy for conversion is to treat every landing page as your home page. One of the best practitioners of this policy is People.com, which gets a lot of traffic in the side door from search, blogs, and RSS. When you hit an internal article at the site, the design sells the brand. You see all the other top headlines, the most viewed celeb stories, with photos in one corner, and you get a module that lets you subscribe to eletters, RSS, and even mobile alerts. The range of People.com resources is there for you. You see the brand's breadth and can drop into a relationship with it in a click. Anyone wanting to convert stray traffic into loyal audiences needs to consider how every page of the pub has to act as a home page and sell the brand.

B2B publishers are particularly vulnerable to the ravages of search addiction, because the engines funnel many less-qualified readers into these specialized content sites. B2B lives and dies on the quality of its audience, but a site's logs can get deceptively stuffed with page views and uniques that are not really in the market for anything the advertisers have to sell. The audience gets diluted. This is going to be a bigger issue as 2007 progresses and more publishers invest in SEM.

Because of the new search economy, sites have to start thinking about better and worse kinds of traffic, and how in the digital realm growing the audience is different from growing the brand.