There was a thread over on the Lake St Clair network (www.lakestclair.net) - news story I saw said the boat hit the rock breakwall, then launched 100+ feet onto the beach, *clearing* a 3 ft fence on the way!
Happened at night after they left Jack's Waterfront - cops said "alcohol was likely a factor". Story is the guy saw another boat in front of him, swerved and hit the beach.
Here's the news story from our local "boat-hating" TV station: http://www.clickondetroit.com/news/4846083/detail.html
More to come, I'm sure...