FB is the most common social website - I'm sure this warning applies to all sites that have password cookies that aren't secure sign on. Just like Microsoft PC s are targets (and Macs are having slightly more problems too) FB is going to be one of the first mentioned.
It's a good idea not to respond to applications on your friend's sites on FB too. Games and Questions on FB like to gather your info. I prefer to opt out of these third party applications.
Thanks for the website Geoff!