By Augustine's day Pentecost was a separate liturgical festival, and Augustine understood it as a celebration of an event no less historical than the birth of Christ. In a sermon preached on the day of Pentecost, he says, we are celebrating "the solemnity of a day so holy, that today the Holy Spirit himself came."- Robert Wilken, The Spirit of Early Christian Thought
The Straight Dope on the seven gifts of the Holy Spirit.
Gifts versus fruits of the Holy Spirit.