Previous posts have highlighted the problems with PowerPoint presentations - or to be fair - the misuse to which PowerPoint is put. For instance see: 25 Years of PowerPoint - A Review by the BBC and How Not To Do PowerPoint.
It is possible to create slides that better reinforce the message of the presentation and that are more memorable. Lists of ideas can be presented in a more visual form, such as a mind map.
Using this kind of imagery also allows the presenter to become more dynamic - working with the image to draw out key points; to highlight different areas as they are addressed; and to make relationships between objects in the image through the use of pointers and movement (waving your arms about).