I recently watched a recorded presentation by Jim Hugunin and John Lam, entitled "Just Glue It! Ruby and the DLR in Silverlight".
The presentation made me wish that more performers would be like Edsger W. Dijkstra, or at least make an effort towards imitating his style. See and listen for yourself, and I hope you'll share my preference. Unfortunately the "demo-oriented" presentation style, in which contrived demonstrations that require nor provide any insight are exchanged for content, is becoming common.
PS I would like to add that, judging from their blogs, both Jim Hugunin and John Lam are intelligent, creative and well-spoken human beings. Which makes their performance all the more saddening: it may be a cultural phenomenon.