This will show you how to talk to your friends using Facebook chat in iMessages on your mac. Facebook chat uses the xmpp protocol. This means that you can connect to Facebook chat using third party chat applications. This makes Facebook chat comparable to the way you used to connect to msn chat using pidgin.

Setup facebook chat in imessages.

  • open iMessages
  • goto preferences
  • goto accounts
  • hit the + in the bottom left
  • select ‘other’ type of account
  • account type: Jabber
  • account name: username@chat.facebook.com
  • open server options
  • server: chat.facebook.com
  • port: 5222

You have now setup facebook chat in imessages! you can log in and talk to your facebook buddies

sources:
wikipedia xmpp page
facebook chat information