The Mar 2009 New Engl. J. Med. describes the great success of kidney exchanges. The article written by Michael Rees and colleagues report in details how in 2007 one donor started a chain that lasted several months and helped match kidneys for ten patients. Dr. Rees is a urologist at Univ Toledo Medical Center (home of the Alliance for Paired Donations that runs the NEAD program) that facilitated this chain.
Videos of national news coverage of paired donations available here.
Schematic of donor chain. Image from New Engl. J. Med.
Reading this article reminds me that I haven’t heard anything from the APD the since May 2008. I send them an email asking what my donor status is.
[Update: The donor chain described above now has 21 participants and is still active. See a Nov 2009 blog post for details.]