Differential dynamic content delivery, including creating a session document for a presentation, including identifying a user participant for the presentation, where the session document includes a session grammar and a session structured document, the user participant has a user profile comprising user classifications and user interests, the user interests comprising data fields for storing data values indicating user interest in one or more subjects of the presentation; receiving from the identified user participant at least one data value indicating user interest in one or more subjects of the presentation; storing in the user profile the data value indicating user interest; recreating the session document in dependence upon the data value indicating user interest; selecting from the recreated session document a classified structural element; and presenting the selected structural element to at least one user participant.