The site's Vying Games (vying.org) if you want to check it out. : ))
I develop a Go web app myself in my spare time: http://eidogo.com/. It's more for studying and bot-playing than multi-player, though.
I decided that since I'd probably never make more than a pittance off it, I'll just give it all away for free and open the source. At least it makes for a good resume item to show off my JavaScript chops.
I plan to add games like Go and Chess eventually. I've tried to focus on mostly lesser known games so far. The Go and Chess communities are very well served, and I'm not sure I could add much for those communities.
Some of my site is open source, btw. The ruby libraries that implement the game rules and bots is available at:
The server itself is closed source, but I plan on adding a well defined http api for outside apps to play there this coming week.