Here are a few exceprts I found interesting - but make sure you click on the link above and read the whole thing.
"In Christian terms, the late 20th century will probably come to be known as the era of the “Pentecostal Explosion.” From less than six percent in the mid-1970s, Pentecostals finished the century representing almost 20 percent of world Christianity, ..."
"That would make Pentecostalism the second-largest Christian “denomination” on earth, lagging behind only Roman Catholicism. There are more Pentecostals today than all the Orthodox, Anglicans, and Lutherans put together. "
"... Harvey Cox has dubbed Pentecostalism “Catholicism without priests,” meaning an expression of folk spirituality without the Roman juridical system or complicated scholastic theology. "
Assuming that the growth trend continues, what long-term effects do you think this will have on the Catholic Church? What would Ecumenical progress look like?