Read original post by Bernardo Zamora at Windows Phone Developer Blog
Microsoft Advertising is committed to increasing advertiser demand and growing advertising revenue for mobile app developers. The latest improvements to increase developer monetization and end-user relevancy have just been released – these involve changes in the pubCenter categories used to target ad units. To fully leverage these new capabilities, developers need to visit pubCenter to take action to select one category for each ad unit and align that category with the selection in the Windows Phone Dev Center. This is a category update only and no app resubmission or certification is required.