Convicted sex offenders aren't a sympathetic bunch, but I expect we'll hear something about the risks of putting their personal information online after a young Nova Scotia allegedly used the State of Maine's sex offender registry to track down and murder two residents of that state who were listed in the registry. The database includes names, conviction information and address. See: CBC News: Suspected killer accessed online sex offender registry.
Update: David Holtzman at Global POV has an interesting comment on this post and the issue in general. See: GlobalPOV: Listless in Maine (20060419).
The Toronto Star's editorial advocates keeping registries private: TheStar.com - Editorial: Keep registries secret (20060419).
Update - 20060421: Tamara Thompson at PI Buzz notes that the Maine sex offender registry has been taken offline. She also discusses that the law enforcement agencies who maintain the site don't have any authority to do so since the Maine law setting up the site simply says that they shall make this information available to the public on the internet. See: PI Buzz - Maine yanks sex offender registry