Slideshare just announced a new service that will allow you to embed slideshows in your press releases. It's free or you can pay $6 to send a SEO enhanced release. You can read details on Slideshare's web page.
A few tips on using SlideShare in press releases:
Make the first slide enticing
Keep it short on a press release, 15 slide max
It's ok to be a tease. Reporters will call for details