1. A system to dynamically display a presentation of a time duration, the system comprising: a processor configured to receive comments associated with the presentation, the comments arranged in a first ordering, to identify a time reference comment among the comments, the time reference comment including a time reference referencing a time instant within the time duration of the presentation, and to dynamically change an ordering of the comments from the first ordering to a second ordering at the time instant; and a display device configured to display the presentation with the comments, the comments arranged according to the ordering.