However we have found these details from a posting on GA Forums

• Core gameplay centered on player choice and customization
• Game takes place in the early 60s
• Dev's main goal is total immersion in the story
• you wake up in the ocean surrounded by debris and your first goal is survival
• something about creatures in the ocean discovered by scientists
• "We're creating a world for to be in. What you do is up to you, and you have to live with your choices."
• One of your skills is agility and it makes you run faster
• most upgrades will affect weapons
• you can create weapons and items
• you can hack stuff by being an engineer
• A walkthrough is useless - you take the game where you want it to go (Sounds really open ended)
• BioShock holds many mysteries
• Xbox 360 and PC - O N L Y

It sounds excellent! I can't wait to see some screenshots!