http://googledocs.blogspot.com/2008/04/view-your-presentations-and.html

http://www.google.com/google-d-s/whatsnew.html

Google automatically comments out some CSS, like body background.

http://googledocs.blogspot.com/2008/04/view-your-presentations-and.html

[Unlinked signature URL: friendcredit.com – Colin]

There is also the Speaker's Notes thing

http://www.google.com/google-d-s/images/new_presonotes.gif

It would to have some CSS templates or make some gallery where people could upload their styles.
Anyway, I'm really happy about this feature, it brings gDocs much higher. I missed the ability to easily change document theme to something nicer than the default one.

Now you can also save a presentation as PPT! (which is a very important feature)

[Name updated to link with older posts – Tony]

orliyakuel
That's been around for about a month, but before that I wasn't even thinking about using Presently

there is two more new features also there
(1)Add Speaker notes for your presentations.
(2)View your presentations and spreadsheets offline.
you can more information here
http://readerszone.com/office-suite/new-features-introduced-in-google-docs-2.html