If you have a Rich Text Editor (or actually any XML-based data type) on a media type the XML/HTML-content gets stripped in the output. The issue is described here: http://issues.umbraco.org/issue/U4-644
Temporary workaround (also taken from the link above):
@{ var mediaFromDatabase = new umbraco.cms.businesslogic.media.Media(slide.Id); }
@Html.Raw(mediaFromDatabase.getProperty(”bodyText”).Value.ToString())