There's been some fascinating developments in this area in just the past few day...

There's been some fascinating developments in this area in just the past few days. MySpace is now releasing similar data commercially through Infochimps:

http://www.readwriteweb.com/archives/myspace_bulk_data.php

NetFlix get slammed by the FTC:

http://blog.netflix.com/2010/03/this-is-neil-hunt-chief-prod...

and Arvind & co summarize the latest research on why anonymization is (mostly) broken as a security measure:

http://33bits.org/2010/03/15/open-letter-to-netflix/

Big Data is getting bigger...