This is commonly called "Adsense revenue share" because the main interest is to actively encourage people to participate in the forums.
When there are already so many forums out there, this is the sort of feature that really helps to make a difference.
At one of the my forums, sharing the revenue with those who participate has brought an interesting new dynamic to the daily forum activity.
People will look for interesting topics to start talking about because they can actually see adsense depositing some revenue according to the popularity of their topic, while the people who reply last to the topic know that answering to questions made on the forum might also bring some valuable revenue.
It's a win-win situation for everyone involved.
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If this came as default, then it would be a manner of rewarding the forum webmaster, the forum starter and the last forum replier altogether.
On a first sight it might seem that the multi-forum owner won't be making a profit but..
- all forums combined can aggregate a huge number of daily pageviews and it's always possible to include CPM advertising code from other ad networks.
- if people like the service, they'll surely be promoting it further to increase their own personal gains
- if this comes as default, then forum repliers might also participate in other forums of the same network to keep their revenue levels high.
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