In 
September 2016, we will disallow the setting of 
positiveGeoTargetType as 
AREA_OF_INTEREST for non-search campaigns. Existing non-search campaigns whose 
positiveGeoTargetType are set to 
AREA_OF_INTEREST will be automatically changed to 
DONT_CARE. Any requests that attempt to set this to 
AREA_OF_INTEREST for non-search campaigns will fail.
In addition, for search campaigns, the behavior of 
AREA_OF_INTEREST will be changed. If you use this setting, the campaign will 
primarily target a user's area of interest and secondarily his/her location of presence. In other words, if the area of the user’s interest is explicitly present in a search query, such as “flower delivery in NYC”, then it’ll be used. If the search query doesn’t include any areas of interest, say “flower delivery”, the physical location of the user performing the search will be used instead.
If you have any questions or need help, as always, please post on the 
forum or the 
Ads Developers Plus Page.
 Thanet (Knack) Praneenararat, AdWords API Team
Thanet (Knack) Praneenararat, AdWords API Team