Yes. By default, SongShow Plus will play PowerPoint presentations using the PowerPoint playback mechanism.  PowerPoint or the PowerPoint Viewer needs to be installed on the system for the default configuration to work.  The PowerPoint Viewer will only give basic control over playback and is not ideal.

More integrated support for PowerPoint presentations is provided by the PowerPoint Support and PowerPoint Import Plug-ins.  These Plug-ins require that a supported version of Microsoft PowerPoint be installed on the system.

The following versions of Microsoft PowerPoint are supported in SongShow Plus:

• PowerPoint 2000
• PowerPoint 2002
• PowerPoint 2003
• PowerPoint 2007

This list will be updated as new versions become available and are tested.

(FAQ022)

UPDATE:

The September 2009 Edition of SongShow Plus integrated the PowerPoint Support and PowerPoint Import plug-ins into the main installation and eliminated the associated settings to improve and simplify the use of PowerPoint presentations within SongShow Plus.
 
With this change the PowerPoint Viewer will no longer work to present PPT files within SSP.

Editions of SSP prior to September 2009 should still work as before, however, for the best results it is recommended that a full version of PowerPoint is used.  The supported versions of Microsoft PowerPoint are unchanged.