Here's another article calling PowerPoint presentations the very definition of snoozeville.
A previous CIO.com article made the point that over-reliance on slides means you don't adequately know your material. This BBC News article, meanwhile, talks about the bullet-point problem: People can't absorb as much information as text-heavy slides can convey. And such slides often keep the speaker's back to the audience.
It advises focusing on eye contact. And if you didn't already have enough to worry about, here's a critique of tech speakers' gestures.