Update: Google is reminding users of the AdWords API that on April 22, most of the services related to v13 will be turned off. The company is telling users to switch to v200909 quickly to avoid any complications.

Google launched the newest version of the AdWords API v2009 beta. That would be version 200909. Google cites the following as the highlights of the new API:

Asynchronous calls: Asynchronous calls lets you work with large sets of data faster and easier. Instead of waiting for the system to completely finish your request before you’re able to make another one. Now you can make another call as soon as the API service confirms that it received your previous calls. You don’t have to wait for your server to complete large requests anymore. V200909 will continue to support Synchronous methods as well.

Keyword and placement ideas: With the new Targeting Idea Service, you can get keyword and placement ideas through the API, leveraging the functionality of the search-based keyword tool.

Location Extensions preview: Limited location extensions functionality is now available as a preview of the full functionality in development.

These are just the highlights. Google has a complete list of all of the new features in its release notes. The company says that over the next few months, Google will continue to bring new features and additional AdWords functionality. These new features will include Report Service, Account Service and the ability to pre-check for errors.

“Given that v2009 introduces new concepts and features, we have extended the sunset period for deprecated services to 6 months,” Google says. “If you haven’t already begun migrating your systems to the v2009 API, we strongly encourage you to start right away.”

V13 services Campaign Service, Ad Group Service, Criterion Service, Ad Service, Info Service, Keyword Tool Service, and Site Suggestion Service will sunset on April 22, 2010. Other v13 service sunset dates will be announced in due time.