The front page of Shoryuken now includes a number of excellent Strategy Corner articles. A recent highlight of this series is A Quick Guide to Reaction-Based Defense by Thelo, a Canadian HDR player who made top 8 at EVO2009 and mains E.Honda.
As someone who’s playstyle favours the “down-back” position, I found this to be an excellent discussion of the difference between reaction and prediction in fighting games. Even if you prefer an offensive style of play, it helps to understand how to attack to minimise your exposure to reaction-based defense.