A proposed video of Linger in Shadows leaked on to the internet back in March. The clip is eye-catching, but we don’t even know if it’s a proper game. The ESRB just rated it, deeming it fit for everyone. An ESRB rating doesn’t necessarily mean Linger in Shadows will be a game. Linger in Shadows could be an interactive experience like Tori-Emaki, which was also rated by the ESRB. However, Sony Computer Entertainment trademarked Linger in Shadows as “video game software” and “operating a real-time gm for others over global and local area computer networks.”
My hypothesis is Linger in Shadows will be a PlayStation Network download along with the recently ESRB rated Ratchet & Clank: Quest for Booty and The Last Guy.
Update: Andrew Yoon over at PS3 Fanboy explains Linger in Shadows is a PSN project and "it's interactive digital art" scheduled to come out in July.
Images courtesy of Sony.