first person
On Savoir-Faire
Emily Short explains that one of the goals of Savoir-Faire is to teach the player to become a magician. This pedagogical orientation means that - in contrast to interactive fictions that allow only a severely limited range of player input - Short's game rewards undirected play because the player is not only solving puzzles, but also learning.
On Solitaire

Helen Thorington describes Solitaire, a program for generating fiction in the same line as the projects explained by Chris Crawford and D. Fox Harrell elsewhere in this thread.
Pax, Writing, and Change

Stuart Moulthrop argues that Pax answers John Cayley's question, "What would textual instruments look like?" Moulthrop maintains that one plays this electronic text (in the manner of a musical instrument) as much as one reads it.
Fretting the Player Character

Nick Montfort argues that the contentious notion of the "player character" usefully constrains and makes possible the player's interaction with the gameworld. He considers the possibility that in interactive fiction one plays the character (like an actor plays a role) rather than playing the game.
Patterns and Shade
Carl McKinney argues that Jeremy Douglass's analysis of Shade suggests a presence/absence dynamic useful for understanding interactive fiction in general.