We are making a minor change to the values returned in the ClickType column in AdWords API reports. Starting the week of 
May 26th, 2014, AdWords API reports will return "Product listing ad" instead of "Offer" as the display value for click types corresponding to Product Listing Ads.
If you depend on the ClickType field, verify that your applications won't be negatively affected by the change in value.
If you have questions or feedback about this change, let us know on our 
forum or via the 
Google Ads Developers Google+ page.
 Anash P. Oommen, AdWords API Team
 Anash P. Oommen, AdWords API Team