The San Francisco-based company has moved into comScore's list of 25 top ad networks. They are one of the top 5 fastest growing networks, up 40% to 73 million. Granted, this is one list of one metric from one source. And it might not be the best metric. But it's certainly still worth noting. Obviously, uniques do not mean nearly as much as revenue, CPM, customer retention, margin and impressions diversity. Rounding out the top five are Turn Inc., with u.s. unique visitors up 121% year-over-year to 134 million; CPX Interactive, up 88% to 130 million; 24/7 Real Media, up 48% to 148 million; and Collective Network.

Hal Muchnick, president of Kontera U.S., says "Our technology enables us to target against more than just keywords, but also to the semantic meaning of pages-to-content. Because of this better targeting, we can generally serve fewer links per page along with strong campaign performance. Combine this with the fact that we only do business with sites that are exclusive to our network - which grew 40% alone in 2008 and now reaches 73 million u.s. unique users - and you have a winning hand."

In-text ads may be one of the targeted technologies consumers are most comfortable with. Muchnick claims that Kontera's growth is a sign that, in addition to performing for publishers, it is providing real value to consumers, which can be seen in steady engagement rates. "In a world of full-page takeovers, banner fly-outs, pop-unders and pre-roll video, I would say that a user-initiated ad that disappears when a user disengages is consumer friendly and provides good engagement," he says. Kontera provides publishers other products that deliver relevant, related content to users, with the goal of extending the user-experience and value delivered from the site.

So then, what does Kontera have in common with the other big growers on the comScore list? According to Muchnick, very little, aside from the fact that they are all in the network space. "They are outside of the text and we are in the text; they share publishers and we do not," he says. "We have an exclusive relationship with our publishers and ours are unique to us; we offer a unique value proposition that is not commoditized." By not stressing any one metric too strongly, and valuing the overall relationship over the quest for any one goal, Kontera seems to have found a secret sauce for the rocket-fuel propelling it into the realm of the big ad nets.