Matchmaking is generally safer as candidates are vetted by the matchmaking team.

To play on Halo 3 matchmaking you must have a gold xbox live membership and an internet connection to play on matchmaking. If you only have a silver membership it will not let you play matchmaking.

yes you can, Firefight will however be different in matchmaking then in a custom game. The match will usually be on Heroic difficulty and will only be 1 round. but yes you can play with random people in firefight matchmaking.

Of course you can find love with a matchmaking service. The people that use matchmaking services are no different than the people you may find through other means.

Some recommended matchmaking and dating sites are Matchmaker, MySingleFriend and The Modern Matchmaker. Some people also use Facebook as a matchmaking site.