Pens and Swords; fantasy fiction writing. The most recent posts are about World Building and how it varies as a Fantasy author vs DM.
The DMs Blog: The d20 Stops Here.
The Cull: A best of RPG theory discussion blog
Stake setting in various indie games.
Interesting 4e community campaign: Harvestlands, plus an interview on livingdice.com.
Excellent community website for Washington DC