A new Facebook app called What Would I Say answers exactly that question, generating Facebook updates automatically so you don't have to!
It works by accessing every post a user has come up with, mixing them up and regurgitating bits of them in an order that (kind of) makes sense.
Added bonus? It sounds just like you, or how you come across to other Facebook users, according to the developers that built What Would I Say.
“Technically speaking,” its creators say, “it trains a Markov Bot based on mixture model of bigram and unigram probabilities derived from your past post history.”
There you go.
As for security risks, they also reassured users that info is not stores, and all computations are done client side, so only your browser ever sees your history.