Please vote for WS-Eventing if this is relevant to your enterprise web services

http://www-128.ibm.com/developerworks/webservices/library/specification/ws-eventing

The WS-Eventing specification defines a baseline set of operations that allow Web services to provide asynchronous notifications to interested parties. WS-Eventing defines the simplest level of Web services interfaces for notification producers and notification consumers including standard message exchanges to be implemented by service providers that wish to act in these roles, along with operational requirements expected of them.

WS-Eventing specification provides similar functionality to that of WS-BaseNotification. WS-BaseNotification is one of the WS-Notification specifications that were submitted to an OASIS TC in April 2004. The WS-Notifications specifications provide a rich set of functions supporting publish/subscribe required by robust, scalable enterprise applications including message brokering and topic based subscription management.