The model module for Wicket Objects holds the implementations of Wicket IModels, with these IModels wrapping Naked Objects domain objects. These IModels are shared among different views defined in the ui module.
The IModels also handle serialization issues required by Wicket's stateful architecture, storing the state of these domain objects transparently in mementos (even if the underlying pojos are not serializable).
See this module's Javadoc and the user guide for more information.