Celebration of Confession

We were able to listen to Catholic Radio for a little while on our business trip, and the discussion we were listening to was focused on the sacrament of Confession. The priest who was speaking kept referring to it as the Celebration of Confession. At first it kind of confused me by the way he was saying it and then it hit (it didn't take too long, I'm not that dense) as to why confession should be approached with such jubilation of heart (instead of such indignation or anguish).
Think about it, we have done something offensive to God, but in His Mercy and our active participation by recognizing our faults and wanting to rectify them... we are able to come back into union with Him... to reunite our hearts with His Will. If that isn't a reason to celebrate, then I guess I don't know what is!