Here's a very interesting article from the Kotaku website:
First Tiny Look At Linger In Shadows, A Mysterious Real Time PlayStation 3 Demo
German site 4Sceners.de published this weekend the first captured images of a demo for a mysterious commercial product known as Linger In Shadows, created by demoscene group Plastic. Details are virtually nonexistent on Linger In Shadows, a title Sony Computer Entertainment trademarked in November of last year. Members of the Plastic team said of the demo, which was shown at the Breakpoint 2008 gathering this weekend, that it would be released publicly on the PlayStation 3, possibly as a graphical showcase for the system, but that it was not a game in the conventional sense.
Other Breakpoint attendees teased via the Pouet.net forums that it would be somehow playable and that Linger In Shadows was one of multiple demoscene projects commissioned by Sony. We're looking into it further to learn more about the project.