I'm not philosophically opposed to freezing and then reanimating my gray, frozen corpse in a thousand years; and using advanced nano-slush to preserve my already fragile brain isn't particularly repulsive to me, but the logic of cryogenics escapes me.
In a possible future where it is actually possible to revive a pseudo-mummy, how would our beneficent post-cestors decide who to revive? More people would be put in the "deep-freeze" every year, the demand to be revived would always exceed the ability to do so. Even in an utopian society where kindness is perfectly subsidized, they would be forced to decide who would live. How would we repay the investment of a vastly more advanced society? By our labor, intellectual or physical.
Why are we even assuming that such an amazingly advanced society would want our worthless 21st century brains? They would already know that the standardized tests of intelligence left out a lot of essential information; and even people with exceptional native intelligence might be irretrievably damaged by our primitive educational processes.
At best the revived would be parochial curiosities:
"Zoo York" snapshot of the year 2010 with authentic inhabitants."
"Neanderthals, Cro-Magnons and Manhattanites."
We would not be highly valued members of an advanced society; saying that we are signing ourselves up for slavery might be a bit strong, but I can see no instance in history where disoriented, unacculturated and vulnerable people are not taken advantage of.