While marketers have long targeted online radio listeners baed on their zip code or gender, this type of interest-based targeting is new. The ad options, which are the result of a deal between radio service Triton Digital and data provider eXelate, mean radio ads are about to get a lot more specific.

According to Triton Digital COO, Mike Agovino, radio ads represent a $17 billion industry but one that relies on out-dated metrics and that offers little accountability to ad buyers. He thinks that letting brands sell to listeners based on their web surfing habits will drive a new wave of automated ad buying and increase the value of the radio ad market.

The possibilities for radio are intriguing. Recall that, in the recent Presidential election, the parties launched a barrage of political ads in swing districts by using Pandora’s ability to play ads based on a person’s zip code. Meanwhile, their neighbors across the street who lived in a different district might have heard ads for trucks or lollipops based depending on their age and gender (Pandora garners this information when you sign up for the service).

Now, radio ad targeting is going to get even more focused. For instance, the new data tools mean Ford might sell pick-ups after a teenybopper song because the company knows a listener was just looking at truck sites. Or Tampex may find occasions to pitch its products in the midst of a heavy-metal marathon.

According to eXelate CEO, Mark Zagorski, radio is the “last bastion of context based advertising” but that this will change quickly due to online radio’s growing popularity and the capacity of behavioral-based advertising to scale quickly.

As with other situations in which marketers use big data techniques to pitch products, there is a creepiness factor here. For instance, do you want marketers to know you’ve spent the last two hours researching gonorrhea and play you radio ads accordingly? Zagorski addressed the privacy concerns by saying that eXelate doesn’t touch so-called PPI (private personal information) but simply overlays online activity onto a streaming service.

The new interest-based ads will help brands reach users of Pandora, which makes up about 74% of the online radio market, but also the web streams of more traditional radio stations as well.

Last week, New York-based eXelate completed the second round it raised in August with the addition of Trident Capital as a new investor. In August, Menlo Ventures and Carmel Ventures invested $11 million with a commitment to invest an additional $4 million if needed, but Trident was willing to add $5 million, giving eXelate a total of $16 million for the second round.

The company, which was started in Israel, has become more internationally focused and is now firmly planted in New York.

Zagorski has been part of reorienting the company and building its U.S. operations since arriving at eXelate in April 2008. Before eXelate, Zagorski was EVP, CMO at MediaSpan, a software and online ad tech firm. Prior to that, he was president of WorldNow, the leading online network of local television news media properties.

The change at the top comes as eXelate and other businesses in the ad targeting space are facing more challenges from regulators, as consumers are starting to push back a bit more on ad targeting. At the same time, as online advertising continues its comeback, more marketers, especially in the travel and financial services industries, are looking to spend more on targeting. Plus the trend of marketers in general “buying audiences” as opposed to “content brands” like specific publisher sites, is also continuing apace, making services like eXelate’s and its competitors more in demand.