Right, it's a "social game" that encourages intelligent gameplay. Building it as an open platform that others could add logic (say in asm.js modules) would be a cool hook. I'm encouraged by what Minecraft is doing in making a very nerdy game cool, and supplanting mind-numbing entertainment or purely violent games for younger kids. Having something like Minecraft but instantly accessible though the web could be a good way to bring new players into the genre, even if they end up being Minecraft players at some point.