1. An XML management system, comprising: a repository configured to store a manipulatable object model capable of representing metadata about objects in a user's computing environment; user accessible means for manipulating said object model to define and/or modify a) properties of objects thus represented and/or b) relationships between such objects; and means for extending said object model to handle a new type of object by automatically generating descendent class(es) that are able to handle the new object within the object model and incorporating them into an XML management system runtime environment for participation in the object modeling process.