Patric Crispen has put together a presentation about using powerpoint in teaching. He makes interesting points, for example that PowerPoint's 'fancy' capabilities were developed for the business community where the aim is more entertainment than teaching and not for us where the aim is to teach.
He also quotes interesting research findings. For example that students appear to learn less from expanded, fancy powerpoint presentations than pure text slides (see page 33 of presentation), at least on fact based tests.
So in conclusion! He's saying that we should write powerpoint text only (unless images really assist understanding and the text). It is quicker, just as effective and you can save the powerpoint as outline (.rtf format) to give out as a handout, saving time in the creation of these. Take a basic typography or graphic design course and you will be able to create good looking slides with a minimum of images, fonts and colours.