In case you were away for the long weekend and missed it, on Friday Facebook.com announced via its website that it had been hacked:
"Last month, Facebook Security discovered that our systems had been targeted in a sophisticated attack. This attack occurred when a handful of employees visited a mobile developer website that was compromised. The compromised website hosted an exploit which then allowed malware to be installed on these employee laptops. The laptops were fully-patched and running up-to-date anti-virus software. As soon as we discovered the presence of the malware, we remediated all infected machines, informed law enforcement, and began a significant investigation that continues... We have found no evidence that Facebook user data was compromised."
This means that the old saying still applies: a chain is only as strong as its weakest link. In this case, your sensitive personal information on a social networking site is only as secure as the weakest (mobile or website) app developer.