Good question. The motives for various brands will likely be different.
I had Dove in mind specific because it seemed like a good fit. Take a look at this video: http://www.youtube.com/watch?v=iYhCn0jf46U. It summarizes Doves message in a nutshell I think. They might be interested in your thing because it helps position their brand in front of their key audience (which I suspect are young women and your quantcast data shows a major of your audience were also young women) in a way that supports their message without the repulsiveness of commercials or banner ads.
In addition, the social media managers of these brands would love the opportunity to increase engagement with their audience. On a personal level for the managers, it would give them specific metrics they could reference when talking about how their social media efforts are going. On a company-wide level, the more deeply they connect with their customers, the more products they'll sell.
If you did go down the road of talking to brands, I'd position your product as similar to the OldSpice man campaign but a different tact.
I had Dove in mind specific because it seemed like a good fit. Take a look at this video: http://www.youtube.com/watch?v=iYhCn0jf46U. It summarizes Doves message in a nutshell I think. They might be interested in your thing because it helps position their brand in front of their key audience (which I suspect are young women and your quantcast data shows a major of your audience were also young women) in a way that supports their message without the repulsiveness of commercials or banner ads.
In addition, the social media managers of these brands would love the opportunity to increase engagement with their audience. On a personal level for the managers, it would give them specific metrics they could reference when talking about how their social media efforts are going. On a company-wide level, the more deeply they connect with their customers, the more products they'll sell.
If you did go down the road of talking to brands, I'd position your product as similar to the OldSpice man campaign but a different tact.