The author of Public Speaking Skills for Dummies! says he doesn’t have a problem with slides, as long as they enhance what the speaker is saying.
His biggest complaint is that the slides should complement what the speaker is saying, but often there is one thing on the screen while the speaker is saying something else.
He also makes a point that has long seemed obvious to me. Why would someone bother attending the presentation when they can read the PowerPoint deck and stay home?
Read Alyson Connoly’s article.