Beta 4 Previews at Photoshop world.

http://www.oreillynet.com/digitalmedia/blog/2006/09/post_1.html
Not being in the inner circle and being on holiday, I'm not the first in with this. Thanks to MethodPhoto for the link.

Jeff Schewe also mentions some of the new features including Vibrance and Fill Light from Raw Shooter and a new Curves tool:
"Yes, Beta 4 was indeed demoed today at Photoshop World...pretty cool new stuff too...Fill Light and Vibrance in Develop as well as an entirely new cruves UI with on the curve or on the image adjustments...George Jardine will be demoing B4 the next couple of days as well..more info later."
Andrew Rodeny, Author “Color Management for Photographers”, says of the new Curves UI, "Nothing like it I've ever seen. Super intuitive and powerful".
My mouth is watering at the prospect. Hopefully Jeff will get time to post more information soon seeing as the Beta is being shown in Public.