That's right folks, a Japanese site has (bravely) posted some screenshots and video footage of the new UI features in Longhorn and exactly how it behaves. You can see from the screenshots and videos that the Windows in Longhorn can be stretched, flipped and spun around. At the end of the screenshots and videos is a note to show this is infact build 4015. Indicating this kind of UI is already available in Longhorn builds at the moment. However this build is different to the build that leaked to the internet a few weeks ago, this is a Lab6 build whereas the leaked edition is a main build.
The shots and videos show that core to Longhorn itself is the element of it's new UI developing. The fact DX9 can handle this kind of animation and the animation we have seen in technologies like the slideshow on the sidebar is amazing. As Longhorn is currently at Milestone 5 I am sure between now and Milestone 7 we'll see these kind of animation features of the next Windows even more. I'm not sure if we'll see these kind of windows animation features for the final product but this is a demonstration of just how powerful the animation effects in Longhorn will be.
Screenshot: Calculator Stretched (minimal processor usage)
Screenshot: Calculator Standalone (minimal processor usage)
Video: View window stretching video
Video: View Windows doing the twist
Screenshot: Confirmation of build 4015