In a recent thread the question of Friday abstinence arose, and I must admit that the answer to this question seems to be a jealously guarded secret. Not only was the Friday penance NOT rescinded, it was actually made more meaningful–rather like the Beatitudes not replacing the Ten Commandments, but actually strengthening them.
Our Bishops put our a pamphlet entitled, "Penitential Practices for Today’s Catholics which supports this. usccb.org/dpp/penitential.htm
"If we are serious about embracing the penitential discipline that is rooted in the call to discipleship, then we will identify specific times and places for prayer, penance, and works of charity. Growth in spiritual maturity demands a certain level of specificity, for it shows that we take seriously God's call to discipline and are willing to hold ourselves accountable. In our Catholic tradition we specify certain days and seasons for special works of penance: Fridays, on which we commemorate the death of the Lord, and Lent, our forty days of preparation for the Easter mysteries. Recalling our Lord's Passion and death on Good Friday, we hold all Fridays to have special significance. Jesus' self-denial and self-offering invite us to enter freely into his experience by forgoing food, bearing humiliations, and forgiving those who injure us. Through the grace of the Holy Spirit, the principal agent of all spiri-tual transformation, this can be done—and done with a spirit of quiet joy. For Christians, suffering and joy are not incompatible.
Another source of information on Friday Penances can be found here: ewtn.com/vexperts/showmessage.asp?Pgnu=1&Pg=Forum9&recnu=22&number=443945
One way to understand the new directives is that giving up meat is not penitential for those who are vegetarians, nor should simply abstaining from meat take the plave of living out our call to mission–we should also practice forgiveness of hurts, almsgiving, and the other spiritual & corporal acts of mercy. In effect, the Church still finds exemplary, Friday abstinence in honor of Jesus’ sacrifice for us, but also exhorts us toward acts of charity among our fellow man.
Friday penance is still on the books, and acts of mercy on Fridays are greatly encouraged. If we are not managing to squeeze in Friday acts of charity, I would think a bare minimum would be to remembber our Lord’s Sacrifice for our sakes with abstaining from meat or another more meaningful substitution.