If you built an application on version 2.3 of the Management API, you need to take action.
Starting Wednesday, December 21st 2011, we plan to forward all the Management API v2.3 requests to version 2.4 of the API. This change will be rolled out gradually, and we expect that in a week or two, all the v2.3 requests for Management API will return a v2.4 response.
Version 2.4 of the Management API has the same XML output as version 2.3. The main differences are: