These presentations are very popular now and can be used to insert a flash movie with e.g. your birthday pictures. If you send your flash movies this way most people would be able to see the movie without the difficulties of opening a flash movie in internet explorer. A lot of people can't open a flash movie without some instructions.
To insert a flash movin a Pp presentation go to the View menu, Toolbars , choose Control Toolbox. Then click on More Controls. Choose Shockwave flash object and define the box in which the movie will be shown on your slide. Now go within the box with your mouse and with a right click select Porperties. Set all the parameters like EmbedMovie and Playing to True and in Movie enter the path to your swf file.
Hopefully this will help you in attracting more people in making swf movies.