The html viewlet sometimes does not display rich text but does display the html version. For example,

<div>
<span>Create your major project story items</span><br>You
will need to set up a story item for each of your projects/tasks.<br><ul><ul><li>Summary: <span>ProjectSummary</span><br></li><li>Type: Story</li><li>Filed against: Be sure you file the work item against your product category.</li><li>Tag: <span>ia-project</span><br></li><li>Owned by: you<br></li><li>Planned for: Select the <span>current </span>iteration (by month).<br></li><li>Due date: Enter a due date if there is a specific date</li><li>Status: Ensure this is correct (In Progress, Resolved, etc.) <br></li><li>Description: Add any comments on this  project.</li><li>For related work items, make sure to set the parent ID to this story item<br></li></ul></ul></div>

does not display in the rich text version, but does display in the html version and does render correctly when the viewlet is saved.