They are free on your Mac. iPhoto, iDVD and iMovie can do it. FCP can do it with a lot of creative control. You can use jpgs with FCP.
There also other 3rd party programs that can make slideshows for the Mac. Google slideshow and Mac.
Quality of photos are as good as the originals.
Steve Eisen
Eisen Video Productions
Board of Directors
Chicago Final Cut Pro Users Group