Founded by Levi Kornelsen, the GameCraft forum is an interesting community. Describing his vision for the site, Levi says: “Tabletop RPGs are basically this giant pile of stuff people do, which they have all these different views of. They talk about the views a lot. We’re here to talk about the stuff they do.”
It’s an interesting focus, and GameCraft has a thoughtful, welcoming atmosphere — one example being a post for new members reminding them that they’re already experts at talking about how they play. I admire Levi’s approach, from mission statement to structure and overall feel.
The Toolkit forum seems to include the most threads for GMs, with topics like what constitutes traditional GM prep and starting a campaign. Although it’s still a fairly small community, there’s quite a bit to see.