Update: Here is the announcement from the Google Docs group and from the Google Docs blog.
When you’re ready to share your presentation with your friends, customers, or even the world, it’s easy to do using the familiar Google Docs interface. You can even walk your audience through the slides online in real time. Participants simply click a link to join and follow along, and everyone can chat about the presentation together.
We’re excited about making presentations available today in response to your requests, and we’re looking forward to rolling out updates and improvements to this feature over the coming months. Or, as my son likes to say, “Google. Slide. Weee!” We hope you’ll feel the same way.
(Via Josh Bancroft - looks like he scooped TechCrunch and everybody else!). Just saw this on Josh’s feed and indeed, I can now create presentations in my Google Docs account thanks to the rather sudden launch of Google Presentations! We will see the blogosphere light up with excitement tonight after a day of boredom at the TechCrunch conference.
Screenshots: 
Some first observations:
Simple, Google style interface.
No fancy transitions as far as I can see.
A good number of useful, mostly business oriented themes.
Printable view is a nice feature.
Very fast - definitely has a desktop application feel to it.
Overall: simple, straightforward, easy to use and reasonably powerful. The collaboration functions will make it a winner.
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