You should design a presentation for an online audience in a different way than those for a live audience. Software such as Adobe After Effects are bringing the graphical tools traditionally used in professional video animations within reach of everyone. As an example, see this recent video produced by Paul Durban: a teaser to get people to download an ebook created by the members of Seth Godin's triiibes community.
Two more examples of motion graphics:
A few observations:
  • The text-only animations are very useful for high energy, very short commercials. The bombardment of animations can carry one message across. "This tribes ebook contains a lot of questions, what was that tinyurl again, let's back up". "Got you, women are an underused resource in the 3rd world, we should help them help themselves rather than relying on food aid". Software opens this genre up to the masses.
  • The real master pieces are the ones that include images and artwork (like video number 3). I think these remain highly specialized projects almost similar to TV commercials that can only be executed by animation professionals.
  • (Amateur) presentation designers can still learn from these techniques. See how they use fonts, spread messages over different slides and create subtle transitions between slides that are far different from the spectacularly animated PowerPoint effects.
It is interesting to see how the Girl Effect video tries to make up for the lack of images: it constantly encourages you to imagine/visualize things ("No go ahead, really, imagine her") . See my review of the book Brain Rules, describing the difficulty the brain has with processing text.