Maybe you have heard about this days-long "revival" that happened at a protestant college. The last I heard it was a chapel "prayer and song" service and it kept going for a few days. The people who attended are talking about it like they are experiencing the Second Coming. I honestly hope it does lead to a deeper appreciation of God and His ways, no denying it. Yet, there are some other things that we need to consider.
Firstly, the Mass has been going on for 2000 years now. When you consider the fact that the Sacrifice of Christ occurred on the altar of the Cross, and then was continued once the Mass began on that first Pentecost, we come to realize that it has been going on steadily since then. In addition, when you consider the number of Catholic Churches that exist in the world, in every time zone on this Earth, then the Mass has been going on without stop 24 hours a day for centuries. This is not a competition, it is just a matter of putting things into perspective. For a group of protestants to get all excited and call it a "work of God" when they decided that their pop music concert needed to keep going, is a bit imbalanced.
Secondly, what is it that is keeping this going on? I am not saying anything against a work of the Spirit (depending on what "spirit" it is!), but we are not speaking about anything more than singing and a prayer now and then. Thus, that which is keeping it going on is not terribly different than what kept the Woodstock festival going a few decades back: social entertainment.
Thirdly, when you do not have the Eucharist present in your Church, you get excited about every little "spiritual" movement because that is all you have. I truly wish that our protestant brothers had the Eucharist (but then, they would be Catholic, right?), but without it, there is nothing left to recognize the signs of God except wholly subjective activities. This is why we have the Sacraments: so that we can know through physical observance that a spiritual event is occurring.
Finally, what will happen when it ends? That is the real clincher. Anyone who knows the history of the protestant revivals of the past (e.g. the "great awakening" etc.) knows that the hype fades, and people go back to their previous lives. What I want to see is not people excited, but people becoming more godly. People not just enjoying the party, but people impacting the world around them with holiness. If this happens (as it did on the first day of Pentecost--Acts 2) then we should take notice. Short of that, it is just a very, very long party.