Facebook keeps rights to your content - even after you leave
That last word there is the scary bit. Previously, under the old terms, an important phrase regarding the termination of a Facebook user account stated,
You may remove your User Content from the Site at any time. If you choose to remove your User Content, the license granted above will automatically expire, however you acknowledge that the Company may retain archived copies of your User Content.
However, this phrase no longer appears under the new Terms of Service, suggesting Facebook now retains the right to do whatever it wants with your content regardless of your account status.
Users have (hopefully) always been aware of scary license speak such as this,
You hereby grant Facebook an irrevocable, perpetual, non-exclusive, transferable, fully paid, worldwide license (with the right to sublicense) to (a) use, copy, publish, stream, store, retain, publicly perform or display, transmit, scan, reformat, modify, edit, frame, translate, excerpt, adapt, create derivative works and distribute (through multiple tiers), any User Content you (i) Post on or in connection with the Facebook Service or the promotion thereof subject only to your privacy settings or (ii) enable a user to Post, including by offering a Share Link on your website and (b) to use your name, likeness and image for any purpose, including commercial or advertising, each of (a) and (b) on or in connection with the Facebook Service or the promotion thereof.
But in theory, at least, under the old terms, one could always rely on a simple account removal if ever concerned about their content. Theory no more. What's yours is theirs and what's theirs will always be theirs.