Bonus DVD Disc Two:
• The Art of Perfect Dark Zero video feature.
• Kepi & Kat music track from the game.
• Perfect Dark Zero Gamer Tiles to customize your identity on Xbox Live.
• Perfect Dark Zero Heads-Up display (HUD) UI Skin to customize your Xbox 360 experience.
• The first chapter from the new novel, Perfect Dark:Initial Vector.
Click on the link for the screen shot, which looks like some sniper scope being used.
http://news.teamxbox.com/xbox/9071/Perfect-Dark-Zero-Limited-Edition-Content-Revealed/
The Gamer Tiles I think are for your name display on LIVE. Currently with Halo 2 if you register with Bungie for stat tracking, your background name tile shows your registered at Bungie when playing on LIVE. I guess with PDZ you'll be able to customize it different ways which is cool for clan members that all want to have the same background.