AdWords API Advisor informs us via Google Groups that Google AdWords API v13 has been released. Though mentioned in the release notes, the these new features include enhanced geotargeting options, ability to retrieve only active campaigns/ad groups, campaign budgeting suggestions, new report types, mobile image ads, quality-based bid/Quality Score support, and more.
On a somewhat related note (but not really), the AdWords API Blog announces that in time for the holidays, Google is offering a bonus of 20% more API units at no additional cost through January 15. Forum discussion continues at Google Groups and WebmasterWorld.