Content from DEF CON 19 can now be watched on a free DVD file posted to the DEF CON website. They released two versions. The first is the original DVD they were distributing at the conference. The second has all the same content, but with the updated slide decks from the speakers and is about 100 MB larger.
You can find a list of the speakers and a brief on their presentations here.
The first video can be downloaded here (1.6 GB):
The second video can be downloaded here (1.7 GB):