The W3C published their "requirements" document for web services choreography:
This just might be the biggest piece of crap that I've ever had the misfortune of reading. I'm not just saying that because I think that the W3C should get out of the business of 'business process languages' - I mean it.
Seriously - look at the document. Remember it is a requirements document. I've read it twice now - for the mercy of spec readers everywhere - can someone please kill this working group???