This page is for PowerPoint, Keynote (Mac) and any other software you might use during a presentation.

Microsoft PowerPoint 2007 (or PowerPoint 2008 for Mac)
PowerPoint is definitely the most standard presentation software and does a fair job in presenting your information.
Good: Widespread use, lots of support, not hardware or knowledge intensive to create basic presentations (pictures, small mpg video clips, bullet points), somewhat versatile, improved greatly from 2003 version for ease-of-use
Bad: Not real intuitive (many new users or infrequent users find it difficult to create polished presentations), default file format (pptx) is not compatible with 2003, hard to automate any repetitive slide component creating, poor fine-tuning menus (or ribbons as it's now called) - the basic functions are great in the new ribbon format, but not the advanced functions. Very poor chance of correcting an "inherited" PowerPoint presentation unless the creator used the master slide function - more than likely the presentation has evolved through several renditions and you'll have a hard time easily updating.

Learn more about Microsoft PowerPoint features, FAQ, resources, etc.

Bottom line: If you need a quick presentation or a real basic one, PowerPoint gets the job done with ease. You can quickly make yourself familiar with the new ribbon-style menus and will not have too many frustrations in creating your average presentation. However, if you think creatively "outside the box" then save yourself some time and frustration in the long run. Your elaborate plan may or may not play out well in PowerPoint 2007. Poor planning on Microsoft's part with the pptx and ppt file types - make sure you save a version of your presentation as a ppt file if you will be using someone else's system to present.

Keynote (Mac) 2009
Keynote is becoming a standard for advanced, polished presentations - particularly with media usage. Keep in mind, this is based upon one person's experience, but more and more presenters have been using Keynote at churches and schools for presentations.
Good: Great support from the Mac community forums, integrated with other iLife 2009 and iWork 2009 programs, in-depth tweaking is easy, good themes and overall polished feel. In slide show mode, Keynote provides a timer, syncs with iPhone/iTouch to use as wireless mouse (on WiFi currently but Bluetooth soon), and uses "media placeholders" that allow for quick swapping of pictures and video while keeping previous proportions and sizes simply by dragging and dropping.
Bad: Only for Mac, PowerPoint cannot open Keynote native presentation files (although default menu allows you to save them as Microsoft .ppt files easily), user must learn a new editing system.

Learn more about Keynote 2009 features, FAQ, resources, etc.

Bottom line: If you have a Mac, why would you use anything else? It's the easiest option for Mac users since most come with iLife programs and iWork suite is cheap ($100 or less) and they work together seamlessly. Easy to edit photos and video right in the program itself and allows for duplication of components and actions quickly. It would be nice if there were a "styles" option, but otherwise it is a great presentation program.

Impress (Open Office Suite)
Open Office is a full FREE office program suite that has a PowerPoint clone called Impress. Sun Microsystems is the creator and it functions very similar to the Microsoft Office 2003 suite.
Good: It's free, universal (Mac, Linux or Windows), and it does everything that PowerPoint will do, it has great potential to grow and have add-ons since it's open-source. Impress allows you to save in multiple formats, making it quite compatible with other presentation software.
Bad: Many of the same negatives that PowerPoint has

Learn more about Impress (part of Open Office suite) features, FAQ, resources, etc.

Bottom line: If you don't want/have to use PowerPoint or the Microsoft Office suite, this is a free option (along with the other programs in the office suite) that gets the job done. Lots of support is available since it's open-source and the community is great. A huge plus that it works on Mac, Linux or PC. It may not have the same polish as Keynote, but it does have a lot of customization and free resources.