Ok, so the anniversary was about a week ago or so, but The New York Times just ran a pretty good overview of the encyclical and its stronger-than-expected "legs." It was written by John L. Allen Jr., who is pretty widely recognized as one of the better journalists covering the Vatican and Catholic "megatrends." He also happened to have grown up in our general neck of the woods and just recently moved to the Denver area. I've liked much of what he's written, though I could generally do without his primary venue, National Catholic Reporter.
Anyway, the whole story can be found at The Deacon's Bench. Also, note Deacon Greg Kandra's reference to Cardinal Stafford, who was the host bishop for WYD Denver in 1993.