Drupal has been making waves in enterprise circles as the collective work of the community allows developers to prototype web applications very rapidly and move them into implementation with few extra steps.

At Brightonart we are being asked by our clients to make Drupal's library of UI tools available to other applications by connecting through web services such as REST and SOAP.
Our biggest goal is to make Drupal seamlessly connect to external data sources, internal applications and third party enterprise tools, whilst still enabling all it's funky features including Views and CCK and a plethora of useful contributed modules for rapid UI development.

Services 3, the development version of Services module disconnects the data source (resource) from the interface (server) which allows us to easily implement a mapping between external data objects and drupal resources (nodes mainly but also users). Services 3 ships with REST and XMLRPC but we need SOAP so I have committed a prototype Soap Server for Services 3 in the Soap Server module (thanks ilo ;-).

Currently the module generates a very simple WSDL from a SOAP endpoint you create with XSD:any types for response and request, but this functionality will be enhanced to provide more detailed data type information from the CCK field information.

I predict interoperability and enterprise integration as big buzz phrases in the next phase of the evolution of Drupal. More on this soon.