Earth to athiests, earth to athiests...
It is indeed true that no one can prove there is a God.
But no one can prove that there is not a God.
So shut the f...er...shut your smelly Obama.
It's usually better if you state this in the positive-sense. i.e., It is impossible to prove that the natural/material world represents the total of reality.
That pre-empts the "can't prove a negative" arguments from small-minded people.