Thanks to writing seven editions of my "iPhoto Visual QuickStart Guide" since iPhoto's launch, I've talked to a vast number of iPhoto users. One common theme among those conversations is dissatisfaction with iPhoto's slideshow capabilities, even as Apple has enhanced them over the years. You can't add text to a photo in an iPhoto slideshow, or add narration, for instance, both of which are frequently requested features.
A powerful answer to iPhoto's slideshow limitations comes from Boinx Software, in the form of FotoMagico 3, which comes in Home and Pro editions. At a basic level, the $29 FotoMagico Home starts with essentially the same features as iPhoto, but builds from there. You can add images from iPhoto or the Finder, mix still images with movies, apply the Ken Burns Effect to pan and zoom on both still images and movies, put text titles on top of your photos, use jitter-free transitions, and lots more. Apart from just showing your slideshow in FotoMagico, you can also export it to YouTube, a Web-based movie, or for display on a DVD, iPod, iPhone, or Apple TV.
But while FotoMagico Home can do much of what most people might want, the $149 FotoMagico Pro adds the truly cool features, like being able to record narration directly within the program, watermark images during the slideshow, and display a teleprompter on one screen while showing images on another. FotoMagico Pro also extends the export options significantly and comes with a license for Boinx's PhotoPresenter, which lets users make template-based slideshows in seconds.