Briefly: During a presentation put on by Sony at CES, they showed the capabilities and the new features of Blu-ray players, and Pixar got a moment to speak. Lasseter discussed Disney Digital 3D and the Blu-ray format. But, even more exciting than that, he showed us an extended clip from Pixar's upcoming feature Up. Here it is:
It is directed by Pete Docter and is set for release on May 29, 2009. See the trailer here.
Update: Oh no! The video has been removed! Probably due to legal issues... Oh well. Still feel free to follow the link above to watch the trailer.
Source: The Pixar Blog