The Mozilla Community Phonebook (planned to be an installation of the Domesday software) will allow community members to create a simple profile about themselves. Mozilla is now large enough that we feel that creating a tool to help people learn more about others in the community will make the community feel smaller and more knowable.
You can now sign up to be notified when the ability to create phonebook profiles goes live.
You can read more about the plans for this site on the Mozillians page on the wiki. There are wireframes, code documents, schedules and more.