Leaving us with very little, you can see that the Bioshock 2 teaser has hit the web.  Displaying 3 pictures, you can see a miniature doll looking like a LBP sackboy using a baseball for a head and push pins as part of the mask.  Just taking small notes I picked up on, you can see the letter was dated in 1967, 7 years AFTER Bioshock 1.  So we at least “think”, it’s not a prequel.  Check out the teaser here.  http://somethinginthesea.com/

Here’s some text from the letter (highlight between the [ ] below to see some “possible” spoiler info):

[The image shows a blood-stained invitation on top of a letter. It reads: "You are cordially invited to return to Rapture". The letter has Mr. T written on it, rest of the name covered by the invitation.]

Related posts:

1. BioShock 2; Creepy Screens with a Retro Twist
2. Big Sister on Cover for Upcoming Bioshock 2
3. Keep ‘em coming, New Bioshock 2 Teaser
4. “Bioshock 2″ IS The Name of The Sequel
5. Oblivion and Bioshock on One Disc, $39.99 on July 7th