Bug 134740 [Wizards] PDE product wizard is not obvious to use.
see attached image. The wizard for creating a new product opens with a file name initialized to ".product" which is selected. Generally this would imply that this is a good default but if you start typing you will replace the text with something else that is also a good name. If you require an extension for a file you should add it yourself like the "Export Archive" wizard.
bundles/org.eclipse.ui.ide/extensions/org/eclipse/ui/dialogs/WizardNewFileCreationPage.java
private static final int SIZING_CONTAINER_GROUP_HEIGHT = 250;
	
	private IStructuredSelection currentSelection;
	
	private IFile newFile;
	private URI linkTargetPath;
	
	private ResourceAndContainerGroup resourceGroup;
	private Button advancedButton;
	private CreateLinkedResourceGroup linkedResourceGroup;
	private Composite linkedResourceParent;
	private Composite linkedResourceComposite;
	
	private String initialFileName;
	private IPath initialContainerFullPath;
	/**
	 * Height of the "advanced" linked resource group. Set when the advanced
	 * group is first made visible.
	 */
	private int linkedResourceGroupHeight = -1;
	/**
	 * First time the advanced group is validated.
	 */
	private boolean firstLinkCheck = true;
	/**
	 * Creates a new file creation wizard page. If the initial resource
	 * selection contains exactly one container resource then it will be used as
	 * the default container resource.
	 *