What ending? You mean the one where all the Shrike pilgrims join hands and skip toward the glowing Time Tombs while singing a song from The Wizard of Oz? (No, we're not joking.) That's not an ending; that's just the beginning.
Hyperion ends right before it gets to the good part. The whole book leads up to this confrontation with the mythical—and pants-wettingly frightening—Shrike… and then cuts to black. It's like a two-part season finale of your favorite show. The good news is that you don't have to wait until next season to find out what happens. Just click on over to your favorite Internet retailer and order yourself a copy of Fall of Hyperion.