The fine folks over at Adroll (including our own Brendan Doms) just launched into private beta today. Adroll is a really interesting concept for buying and selling advertising. I got a chance to play with it a few weeks ago while it was still in alpha and I was very impressed. Basically the site takes a page from social networks and blogrolls and aims to improve the online advertising experience for everyone from advertisers to publishers to consumers.

The Holy Grail of online advertising is a perfect targeting system. Advertisers and publishers want to know that their ads are being put in front of people who care (re: people who will click through and buy things) and consumers don’t want to be bothered about things they’re not interested in. Google does this pretty well using their text based relevancy scoring and a small amount of data about the consumer (IP address, language, etc). They call it AdWords and it’s made them a ton of money (AdSense is the publisher facing half).

The problem is that online there’s a trade off between specificity and readership. A website that talks about, say, Northern California Surfing is the perfect place to advertise if you want to reach surfers. But a site like that isn’t large enough to set up and negotiate advertising deals with major surf gear makers. If only there were a bunch of other surfing sites that they could band together with to form a much larger and more attractive virtual publisher. Well, that’s exactly what Adroll lets you do. Similar sites can join together into highly targeted Ad Communities and use their combined readership to attract advertisers that might have ignored them before. There are also Tagrolls, which are similar to Ad Communities, but based on the publisher provided tags, giving an alternative way to target ads. Check out an example of an Ad Community below.

In order to make trying out their service basically risk-free, you can actually use your existing ad platform in concert with the Adroll service. Simply paste in the javascript you use to serve AdSense or Yahoo or whatever ads, set a reserve price for the ad space on your site, and if they can’t match it, they’ll just display your backup ads transparently. Cool, huh?

The idea behind Adroll is pretty neat, but it’s the execution that really sold me on the product. The site design is really clean and simple, navigation is easy, and a lot of effort clearly went into the interaction design. Check out this dynamic summary text when you go to buy an ad:

Very clear and concise, right? Include the fact that Adroll discloses the cut they take for each billing cycle, and there’s a lot of transparency in the whole system for both the buyers and sellers, which in my experience is sorely lacking in the advertising world.

I’ve only described the biggest features of the site, there’s a ton more I haven’t even touched on. Here’s a quick list of some other things I really liked about it:

• Publishers and advertisers also both get an excellent reporting system that makes it really easy to see
• Referral program for inviting in both Publishers and Advertisers
• Tag based searching for advertisers and publishers
• Publishers can find advertisers they think are good matches and offer a free trial

Basically, if you’re an advertiser looking for a better way to target your ads, or a publisher looking for a way to sell your ad space, I’d definitely recommend checking out Adroll.

Disclosure: I’m good friends with their lead developer and they promised me cookies if I wrote up my impressions. However as I’m hungry right now and the cookies aren’t here yet, I think it probably balances out.

Update: TechCrunch finally has a piece up about Adroll too.