Using SSL encryption to connect to social networks like Facebook and Twitter mitigates the risk of your credentials being stolen when you are using public WiFi networks to connect to the Internet. But it creates a problem for enterprises attempting to control the use of social networking because most firewalls and Intrusion Prevention Systems are blind to SSL traffic.
The recent publication of Firesheep, and the subsequent download of over 104,000 copies of the Firefox plug-in in the last 24 hours, highlights this well understood security flaw in the way social networking sites communicate with their users. Firesheep sniffs the WiFi network traffic to capture your user name and the established session ID for any of 26 sites including Facebook, Twitter, Amazon, and the NYTimes. This allows the Firesheep user to access any of these sites as you!! This not only will reveal your personal information to the Firesheep user, but allow him/her to impersonate you.
This article, Firefox Add-on Firesheep Brings Hacking to the Masses, provides a very good detailed explanation of how Firesheep works. The article also describes several readily available tools which enable or force the use of SSL for all traffic to sites that accept SSL. In other words, rather than just encrypting the exhange of identification and password credentials, all traffic is encrypted.
There is no doubt that using SSL is a good privacy protection control. However, SSL encrypted sessions will make it more difficult for enterprises to control the use of social networking because most firewalls and IPSs are not capable of decrypting SSL traffic. In other words, most firewalls and IPSs are blind to SSL traffic. An exception is Palo Alto Networks, the industry leading Next Generation Firewall.