There's a new Web Services Architecture paper just up on on MSDN and its a good introduction to some of the higher level architectural concepts behind the many Web Service specifications which are becoming open standards right now. The nice thing about this paper is that it is largely co-authored by many of the actual Microsoft Indigo developers, so you're getting a first hand account at a high level of what's behind some of the design ideas around the new Web Service specs.

It's a bit of a long paper, but it is a good read.

I've also gotten some comments that there is also a need for more papers to go with this one, but more focused to the business modeler type of audience (who aren't programmers) on how vertical industry business processes fit around the technical web services architecture. Things more to the business standards person like showing how legally binding business transactions relate to technical based web service transaction compositions. 

If you have any comments about what you'd like to see in any more papers we produce, that might go along with with this one, please drop me a comment and I'll see what I can do.

Enjoy the read.