The Electronic Freedom Foundation offers a time line of changes to Facebook's privacy policies. Slippery slopes ain't in it. More of an avalanche.
Terms of subtly, or not so, dubious import are explicated in the Facebook to English guide.
Should a reading of these fill you with grave doubts similar to those I experience, there is a handy guide to opt out.
The real shame is the lack of a true cancellation. Hanging about in deactivated limbo is not equivalent.