Facebook has taken one more step towards creating a free society where everyone knows everything about everyone else. The 
social networking site has now allowed third party apps to access your address. Since app companies want to know you even better, they can now access your phone number too. Although, Mark Zuckerberg has been kind enough to make this new feature "opt in" instead of the usual Facebook practice of "Opt Out".
However, the dialog box for this 'feature' looks very similar to the usual dialog box used for taking your consent for sharing your basic information. Since Facebook has not sent out any formal notice about this new information sharing feature, it is quite possible that the users would give their consent unwittingly. So far, this consent will provide the third party app companies with only your address and phone number, so your friends' address and phone numbers will still be protected. More information about this feature is available on Facebook's developer blog.
Source: GG