From Amazon’s Web services developer connection:

After many years of useful service, the Amazon E-Commerce Service 3.0 (Amazon ECS 3.0) web service will be shut down on March 31, 2008. Since the introduction of Amazon ECS 4.0 in late 2004 the usage of Amazon ECS 3.0 has steadily declined as sites and applications have naturally migrated to Amazon ECS 4.0. In June of 2006 (Version: 2006-06-28), we achieved complete feature and data parity between the two services and are now requesting that all existing sites and applications be migrated to Amazon ECS 4.0 within the next 12 months. Beginning March 31, 2008, we will no longer be accepting Amazon ECS 3.0 requests. The existing maintenance effort saved by shutting down Amazon ECS 3.0 will be re-invested into Amazon ECS 4.0 to allow for the introduction of more features and capabilities.

It seems Google could learn a thing or two here …