Facebook to share user phone numbers, home addresses with third parties.

"Facebook will move forward with a plan to allow third parties to access the personal data of users, the latest in a series of moves drawing controversy over the privacy of its massive consumer base. The feature will permit applications to seek the private data of Facebook account holders, such as phone numbers and home addresses."

One thing I don't quite understand, for what legitimate purposes might an application desire the personal data of Facebook users? Seems very fishy to me. I think users of Facebook should fully understand that, despite their privacy settings, their profile is public and any personal details they add onto the site should already be considered leaked.