On Friday, Google Docs Guide announced in Google Groups that Google presentations has been updated.
We're ringing in 2008 with some new features. You can now embed your slideshow on any website, insert slides from PowerPoint files or other Google presentations to your current presentation, and drag images from any website directly onto a slide.
Here's an example:
The Google Docs blog has more. Not only can you embed slideshows, you can also add subfolders and rename documents.
Forum discussion continues at Google Groups.