Curio and easter eggs from specific levels in the game, not advice about how to design good levels. Pity.
As a side note, the designer responsible for Fort Frolic in Bioshock 1 and The Cradle in Thief 3 (if you haven't played these games these are highly acclaimed, innovative levels) took the role of Creative Director in Bioshock 2.
A note somewhat related to level design that I am always reminded of is OldManMurray's Time to Crate review system for games: http://www.oldmanmurray.com/features/39.html
Looking through my collection of links, I've found this one which is pretty good at describing how to pace a level. http://www.gamasutra.com/view/feature/4024/examining_game_pa...