OpenHatch does some things well: they have a place to store tasks that get people involved on a basic level, and they let you promote your projects. Githacking is built directly on GitHub, however, so we have tons of data about the projects without the maintainers having to keep it updated. We can tell if a project is active, what language it's written in, and what open issues are up without anyone touching the Githacking profile. Github's api is fantastic.