Surprise in Poetry

Surprise, I'm actually posting (to my non-existent audience). I've been wondering a lot about suprise lately in poetry. In some mainstream poetry, I feel like I can almost fill in the blanks, know what's coming. They end with a bird metaphor or they point to some other gentle ephiphany about life. I would rather be whipped around a little more; wouldn't it be fun to have an ending like a crazy Warners Brothers cartoon or something equally absurd. Do readers really want to be surprised, or do they just want surprises they expect and make them feel comfortable? What would a truly unsettling surprise look like, one that made someone puke even. Billy Collins is reading Wednesday at MLK Library in D.C., so I guess I might go. I'll bring my rotten tomatoes -- just kidding.