Visualisieren ist eine Kunst, Präsentieren auch. Den Nachteil, den übliche Powerpoint-Präsentationen haben, kann man mit den Untersuchungen von Sweller zu Cognitive Load untermauern:

The use of the PowerPoint presentation has been a disaster, it should be ditched.
It is effective to speak to a diagram, because it presents information in a different form. But it is not effective to speak the same words that are written, because it is putting too much load on the mind and decreases your ability to understand what is being presented.
— John Sweller

Dadurch, dass in den Slides die Punkte, die der Referierende vortragen wird, meist 1:1 aufgeführt sind, kommt es zu einer auditiven-visuellen Redundanz, die die Merkfähigkeit auf Seiten der Zuhörer beeinträchtigt. Sweller beschreibt es so:

«The redundancy effect is one of the more surprising cognitive load effects with many people finding it quite counterintuitive. Most of us feel that even if additional explanatory material is not beneficial, at the very least it should be neutral. In fact, the addition of redundant information can have strong, negative consequences. The effect can be understood in cognitive load theory terms.
If one form of instruction is intelligible and adequate, providing the same information in a
different form will impose an extraneous cognitive load. Working memory resources will need to
be used to process the additional material and possibly relate it to the initial information. It is likely to be only after the learner has processed the additional information that he or she will be
aware that the activity was unnecessary. At that point, the damage may have been done.» (Sweller, „Visualisation and Instructional Design“, p. 1506-1507)

Auch Educause hat sich dem Thema «Death by PowerPoint» in einer Rubrik gewidmet:

How do you stop „Death by PowerPoint“? We encourage faculty to turn off the bullets and rely instead on each other and their best teaching instincts when creating PowerPoint shows. The result? Enthusiastic faculty are engaging students by turning boring slideshows into classroom activities energized with storytelling, humor, and interactivity! (Quelle)

Weiterführende Links zum Thema finden sich im Medienzimmer oder hier: Lawrence Lessig’s Free Culture Presentation, Dick Hardt’s OSCON Digital Identity Presentation, The Brand Gap.