So, you have a great Windows Phone 7 app or game and you are ready to make a million selling it or showing ads in it. That's great. The key to success is getting people to see your great app. That's where AdDuplex comes in. Promote your app for free by helping fellow developers promote theirs.
So instead of showing some company's ads in your app, you are actually advertising other developers app(s). I think this is a neat idea that may work out. Personally, I would rather help out other developers than some random company.
What do you think?