Passing XML between layers

Well its raining here in Connecticut today so I'll be playing around with some ideas I've had for passing XML to and from my presentation layer and my facade layer. I got the idea from the MS CRM application. Microsoft created an MSDN site that documents the proxy layer (business facade). You can see it here Microsoft.CRM.Proxy Classes.

They publish schemas showing what elements are available for the entity. The data is published as views that the XML schema is mapped to so the UI developer doesn't have to know how the data store, in this case a SQL Server database, is designed. The proxy objects extend System.Web.Services.Protocols.SoapHttpClientProtocol so I think it is making web service calls (another area I haven't touched yet) to another DLL to do everything.

The app is available to MSDN Universal subscribers for free. I can't set it up because my server at home isn't set up with Active Directory yet. I was able to build the two databases it needs.

Has anyone tried this yet? I'm looking for some examples of best practices as well as cheers and jeers for this type of thing. XML itself is pretty simple, but then again so are a lot of things. Just about everything works, but how well is another story. I am by no means good at XML but I have to start somewhere so I'll be taking a few lumps as I learn.

Paul