If you're convinced by the top 10 reasons you should quit Facebook (and then some more), here are some good news for you and every privacy defender in the planet: Facebook is testing instant account destruction. [Facebook wrote to clarify]
This is JUST a test that we are running with a very small fraction of a percent of users. We are constantly testing new ideas, including the placement of various features on the site. One of these recent tests included variations of the delete account option for a very small percentage of people.
Testing potential features is an important part of our product development process, and tells us if they benefit users in the way we think they will, what we might do to make them even better, and in some instances, when we need to go back to the drawing board. Many tests, while very useful for user feedback, don't result in the changing of the product and/or the features within a product.
If it finally passes the test phase, the new account deactivation panel will include a checkbox to "Permanently delete [your] account and all information [you] have shared". In theory, this mechanism will completely take any trace of your social antics out of their database, destroying your Facebook presence right the moment you click "Confirm". No news on their experimental instant fake Facebook tan feature yet. [Ubergizmo]