Neat idea.
One of the problems caused by certain litigious corporations is that a lot of community-developed knowledge about game/emulator compatibility is lost when an emulator project is forcibly shut down. A separate repository for that knowledge, like this one, could help preserve the information.
I'm disappointed that it doesn't show game details unless the browser allows off-site images, and doesn't show any information at all unless the browser allows javascript. This requires users to expose themselves to security and privacy risks in order to use the site. I would consider contributing if they fix this.