Version 2.4 of the Management API is a XML-only API with a few changes over the deprecated Management API Version 2.3. Version 2.4 is mostly backwards compatible with 2.3 and lets you continue to use the existing XML Feeds and Google Data client libraries. Changes from Version 2.3 to Version 2.4 include the following:
You must register your application.
The base URL has been changed from:
Although Version 2.4 supports all the same authorization methods as Version 2.3, we recommend that you use OAuth 2.0 as described in Using OAuth 2.0 to Access Google APIs.
Version 2.4 is much faster than Version 2.3.
Error messages have been improved.
The HTTP error code for Quota Denied errors has been changed from 503 to 403.
The Analytics Management API allows for programmatic access to the Google Analytics configuration data. You can build applications to more efficiently manage large or complex Analytics accounts. Large companies with many properties can automate account setup. Even if you are building a reporting application the Management API provides you tools to navigate your account.