1. A method for information technology (IT) services and social knowledge management using perspectives, comprising: receiving, by a perspective management system via a user interface, an instruction from a user to build a perspective; instantiating an IT object and an activity stream, the IT object representing the perspective, the instantiating performed by the perspective management system running on one or more server machines in the IT environment; responsive to a specific IT object in the IT environment being selected via the user interface, performing a relationship based search in which IT objects within a certain degree of the selected specific IT object are searched and presented on the user interface; responsive to an invocation of a function via the user interface, adding a set of IT objects currently presented on the user interface into the perspective such that the set of IT objects in the perspective represents a portion of the IT environment that is uniquely of interest to a group or the user, the activity stream configured for capturing communications, notifications, and knowledge relating to the set of IT objects, enabling collaboration between users, and facilitating entry and maintenance of information associated with the set of IT objects, each physical or non-physical object in the IT environment represented by an IT object, the each IT object in the IT environment having a one-to-one relationship with an associated activity stream configured for capturing communications, notifications, and knowledge related to the each IT object, the associated activity stream instantiated when the each IT object was created; storing the IT object representing the perspective in an object store, the object store storing perspectives of the IT environment, each perspective of the perspectives having an associated activity stream instantiated when the each perspective was created; in response to a request from a client device communicatively connected to the one or more server machines over a network, the perspective management system initiating a change request, the change request relating to a requested change to one or more IT objects in the IT environment; in response to an impact analysis request from a client device communicatively connected to the one or more server machines over a network, the perspective management system constructing a graphical view for display on the client device showing a potential impact of the change request on IT objects in one or more perspectives of the perspectives; and in response to an approval of the change request to make the requested change to the one or more IT objects in the IT environment, the perspective management system automatically generating a post about the approval of the change request and placing the post in an activity stream of a perspective of the perspectives.