I got this question from a customer: Does Microsoft support Web Services? Here's my attempt to answer that very generic one...
Microsoft is hard at work implementing consistent XML Web Services support across the product line.
On the AD front, there’s already an XML/SOAP interface available via the "DSML Services for Windows". DSML Services for Windows (DSFW) allows Active Directory access using SOAP over HTTP based on the OASIS DSML v2 specification.
You can download from http://www.microsoft.com/technet/downloads/winsrvr/featurepacks/default.mspx
There’s also a lot of talk around ADFS, the Identity Metasystem and the InfoCard initiative, which are all related to AD and SOAP/XML web services. ADFS (Active Directory Federation Services) is a Microsoft implementation of WS-Federation, released last week as part of Windows Server 2003 R2. The Identity Metasystem is an interoperable architecture for digital identity that assumes people will have several digital identities based on multiple underlying technologies, implementations, and providers. InfoCard is the code name for a WinFX component that will provide the consistent user experience required by the Identity Metasystem.
For ADFS details, check http://technet2.microsoft.com/WindowsServer/en/Library/c67c9b41-1017-420d-a50e-092696f40c171033.mspx
For Identity Metasystem details, check http://msdn.microsoft.com/library/en-us/dnwebsrv/html/identitymetasystem.asp
For Infocard details, check http://msdn.microsoft.com/windowsvista/building/infocard
On the Exchange front, we’re including a full Web Services interface with the next generation of the product, which will offer many advantages to the current MAPI, WebDAV and various flavors of CDO. You will be able to start experimenting with this when Exchange 12 Beta 2 is released later this year.
SQL Server 2005 provides extensive native support for XML (including a native XML data type, XSD schema support and XPath queries). There’s also the ability to expose database functionality via Web Services (this is built into the product, not an add-on as it was in SQL 2000).
Our Visual Studio development suite and the .NET Framework include extensive support for creating and consuming Web Services, as well as architecting and implementing distributed systems that leverages them. We also recently released the third version of the Web Services Enhancements (WSE), a supported add-on to provide developers the latest advanced Web services capabilities to keep pace with the evolving Web services protocol specifications. We’re also working on the next generation of the .NET Framework (a.k.a. WinFX, currently in beta 2), which will further enhance our support for Web Services and incorporate and extend the WSE functionality.
For the latest developer-focused info on Web Services, check http://msdn.microsoft.com/webservices