The v200906 API, which we released as a limited beta in June 2009, will be shut down one week from today, on February 2, 2010. The v200909 API, launched in October of last year, is a full replacement for v200906 and adds significant functionality. Read our earlier post covering the changes required for migration.
Don't forget that most v13 services will be turned off on April 22, 2010, so be sure to begin your migration to v200909 if you haven't already.
The AdWords API team is here to help you transition to v200909. Please post your questions to the Developer Forum.
-- Jason Shafton, Product Marketing Manager