BioShock 2 Has Co-op, One Big Sister, No Big Daddies

A NeoGAF member has posted a quick summary of the BioShock 2 details uncovered in the latest issue of Game Informer Magazine.
-You play as Jack Abbott
-Game takes place in 1967, 7 years after the original
-A cutscene starts the game off In New York City as Jack intercepts the Big Sister kidnapping his daughter in his beachhouse. He follows it to the near by shores as it submerges into the water.
-Mark chases the Big Sister with his boat, and follows the bright red light it makes underwater.
-Mark fires a gun at the Big Sister and pisses it off, causing it to wreck his boat, causing Mark to black out.
-Only one Big Sister (Mastermind of game)
-Big Daddies are no longer in the game, but new enemies include dogs and soviets
-Completely new levels of Rapture, including a fully explorable zoo.
-Underwater exploration levels.
-Squid Boss battles
-New weapons and plasmids (Including a telepathy and time control)
-Challenge maps
-2 Player co-op. (No mention on who second player is)
-New Health and Revival System
I really like the addition of co-op, and the mention of only one Big Sister makes me think our new archenemy will be Dr. Bridgette Tenenbaum.

No Big Daddies, though? Hmm.