"Audio from several of the keynotes are available now. Go to the conference sessions for Friday and Saturday and look for the 'Listen Now' button."
Source: Portable Media Expo and Podcasting Conference
Podcasting Expo Audio: Don Katz, Jason Calacanis, Angel Gambino, Doug Kaye, ETC - PaidContent.org
Podcasting Keynote - Jason Calacanis
Portable Media Expo - Flickr