IComponentData - Initializing CComponentData and Displaying the Snap-in Root Node (MSDN)
IComponent - Creating CComponent and Expanding the Snap-in Root Node (MSDN)
IDataObject - Data Objects and MMC (MSDN)
IConsole(2) - Implemented by MMC. Used by Snap-in to manipulate Scope or Result panes. The IConsole passed to IComponent::Initialize represents Result pane. The IConsole passed to IComponentData::Initialize represents Scope Pane.
(Note: Each IComponent and IComponentData gets its own private IConsole(2) interface pointer. Do not mix them.)