I love seeing new attempts at creating a community for game developers, but I see one issue right now - the site seems to have no apparent benefit over http://www.reddit.com/r/gamedev, which has already more than 110,000 subscribers. Where do you guys see the advantage?

I think the same. There is not advantage over others (http://www.reddit.com/r/TrueGameDev, http://gamedev.stackexchange.com/)