Updated with Audio and Video: GSM Hacking @ 26C3: Chris Paget & Karsten Nohl's Presentation: GSM: SRSLY?

The conference wiki is available here:

http://events.ccc.de/congress/2009/wiki/Welcome

More details of the talk:

http://events.ccc.de/congress/2009/Fahrplan/events/3654.en.html

The presentation is available here:
http://events.ccc.de/congress/2009/Fahrplan/attachments/1479_26C3.Karsten.Nohl.GSM.pdf

Audio is here:

http://mirror.fem-net.de/CCC/26C3/mp3/26c3-3654-en-gsm_srsly.mp3

Video is here:

http://mirror.fem-net.de/CCC/26C3/mp4/26c3-3654-en-gsm_srsly.mp4

News story about the presentation:
http://www.watoday.com.au/technology/security/eavesdrop-fears-as-mobile-phone-security-codes-cracked-20091230-lj90.html