Yes. Beginning with version 8.2, ArcCatalog includes an easy-to-use, wizard-style ISO metadata editor.
The editor currently supports only the core elements as defined by the ISO 19115 standard; they include all mandatory information as well as some optional but highly recommended information. The editor only shows documentation elements - elements whose values can be derived automatically by ArcCatalog are not included. Future versions of the editor support more documentation elements from the standard.