There's a new article up over on MSDN under the XML Web
Services section entitled Understanding
SOAP. The author is none other than DevelopMentor XML guru Aarron Skonnard. In the
article, Aarron covers SOAP from a pure XML protocol perspective; no specific
client/server implementation is discussed. Next to only the specification
itself, this is the best piece of reading anyone looking to learn the
protocol should check out.