yes, actually, they fully intend to throw out EVERYTHING after the original trilogy. i'm betting they'll only keep a few selected parts of the prequal trilogy.
according to what I could determine from wookiepedia, threepio's chassis is eighty years old. his personality, however, probably dates from anakin's assembly. I believe Artoo is at least 50 years older.
however, none of that matters, now...it's all been pitched out the window.