Game theory is the method for analyzing calculated circumstances mathematically. It is used in instances such as gaming, where the success of a player is based on the choices other people make.
Regular Blogs
This weblog is maintained by a professor of strategic management at the University of Toronto who writes, among other things, about various aspects of game theory, including negotiated chess.
http://gametheorist.blogspot.com/
Ludology.org - Vidoegame Theory
A weblog by Gonzalo Frasca, a game developer, researcher and entrepreneur who resides at Montevideo, Uruguay and creates games at Powerful Robot Games. This weblog is all about ludology, the discipline that studies everything about the game theory, videogames and other digital artifacts.
http://www.ludology.org
Focuses on game theory as it impacts and is practiced in regular life, with articles about using game theory in order to divide household chores, the battle of the sexes, and why Coca Cola and Pepsi are never on sale at the same time.
http://mindyourdecisions.com/blog/index.php
Aside from postings about algorithmic game theory, this blog also shares ideas on computation and economics. Items include discussions about technical details about all of those topics.
http://agtb.wordpress.com/