The CNN/YT debate occurred while i was out of the country but by all accounts it went really well and the YouTube team did an amazing job! One of the best write-ups of its impact is via Henry Jenkins at MIT - Answering Questions from a Snowman.
Btw, said snowman was subject of a front page WSJ article today. The Journal totally missed a chance to create its trademark dot drawing of the snowman, instead settling for the two brothers who filmed it. Ah, once Murdoch completes the deal that will all change ;-)