AdSense Host API - Google Code: " You choose how you want the AdSense revenue on user-generated pages to be allocated between you and the users creating the content. In addition, you will earn referral bonuses for referring new users to AdSense.
Engage your community. By allowing users to share in the revenue generated by their actions on your site, you are encouraging them to be more engaged with your program. Users are motived to create more high-quality content and to be more active on your site, leading to increased adoption and traffic."
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