As announced in October, we will sunsetting all versions of the AdWords API prior to v201109 on February 29, 2012. To help you prepare to migrate to v201109, we've created a checklist that covers all of the required changes:

Required Changes:
  • Migrate all API calls to use v201109 services
  • Migrate all API calls to use clientCustomerId (instead of clientEmail) to identify an account as the target of an operation (Blog post)
  • Migrate campaign geo target creation and identification to use the new location criterion object (available through the CampaignCriterionService and the LocationCriterionService)
  • Migrate all other campaign targets (except ad scheduling) from the CampaignTargetService to CampaignCriterionService using the appropriate criterion objects defined within that service*
  • Migrate cross client reporting to v201109 AdHoc (single account) reports (Blog post)
  • Provide developerToken as HTTP header in AdHoc report requests
  • The last few API releases have seen various services migrate to generic selectors, as you update to v201109 you’ll need to migrate from service specific selectors to generic selectors as required. See the Selector Migration Reference for details
  • Update to the very latest version of the AdWords API client library specific to the programming language(s) that you use for API tool/platform development**
  • If you generate your own client side stubs from the API Service WSDLs, make sure that your requests strictly adhere to the WSDL definition as we have implemented stricter validation for the SOAP header and envelope (Blog post)

Optional Changes:

Note: If you do not make the required changes, calls made using versions of the AdWords API prior to v201109 will return errors after February 29th 2012

Additional Notes:
*In v201109, most targets become criteria, with each having it’s own ‘type’ of criterion object (see this Blog post for more details)
**This is an important requirement, so do make sure to check the version of the library or libraries that you are using against those available here