The Prism architecture lack for the Interactions!
The defect opens a popups more then once and creates memory leaks.
Example of the lack here.
The leaks are created by making a strong reference to a thrown views through implicit event subscribtion.
Workaround: Clean the DataContext on a control Unload event (For example by setting the DataContext to the null)
Scenario: You have changeble Views for one ViewModel. You create new viewы for the same view model object.
The Prism Interaction Lack - work example
To download and run the example by yourself click on the "SOURCE CODE" tab above and then click the "Download" link under the tabs.
At the downloaded archive will be the Visual Studio 2010 solution with a Silverlight project.
Run it and follow the simple instructions on a window.
The example's screenshort: