The following components don't have the "description" element in the component descriptor. This causes plugins like "Tapestry Palette" and others to don't display any documentation for these components. I'm sugesting some documentation for this elements below that is basically a copy-paste of the documentation from the site:
Renders the body of a Block component, which may be selected dynamically. The Block may be on the same page as the RenderBlock or on another page entirely.
Renders the body (static HTML and components) wrapped by the container of the RenderBody component. Components which have HTML templates and can wrap other elements should include exactly one RenderBody component in their template.
Provides a form Date field component for selecting dates. DatePicker presents a drop down monthly calendar for users to select dates from.
I would be most apreciated if any of the developers would include this for the 4.0.1 release.