pubCenter is the portal for developers who wish to the Microsoft Advertising platform to provide ad campaigns for their websites or applications (Windows Phone 7 and Windows 8). pubCenter provides information on how to integrate ads into app and tracks ad performance. Revenue is earned when a user clicks on an advert, and a payout made once a minimum threshold level has been reached.
The expanding access to Microsoft's in-app advertising solution should result in more free applications being released for Windows Phone because it provides an additional revenue generation option for developers. The addition of Brazil to the supported countries is especially noteworthy; not only does it has a very active mobile development community operating on an international scale, it is a very large market in its own right.
In addition, for a limited time, Microsoft Advertising is offering developers, who have opened an account with an incorrect country of residence, the opportunity to transfer their account to the correct country.
The image below shows a table of the full list of supported countries, together with payment threshold and currency.
Other in-app advertising options for Windows Phone, which developers may wish to check out, include Millennial Media, AdDuplex,Google's AdMob and Smaato.