If you are not familiar with the Web service Workshops that Microsoft and others are putting on to nail down the details and get public feedback on the various Web service specifications that have been proposed, then make sure you check out the Workshops page on the MSDN Web Services Developer Center.
We recently posted the announcement of a WS-Eventing Interoperability Workshop where people who have created WS-Eventing implementations can try them out against each other. The Workshop is scheduled for April 15th in Redmond.
Next week is the WS-Federation Passive Profile Interop Workshop, also in Redmond.
If you take a keen interest in any of the higher level Web service specifications then you should definitely check out all the information on Workshops that are posted. Included are all the slides from previous feedback Workshops.