its still growing, yes? plus, considering that both china and india (which account for what 1/3rd of world population?) *have* and *do* use population control measures (or programmes), which those chris is responding to oppose, you should adjust the above numbers to include the "missing dead" (if that's the right term i have heard used).
i do not know about the mass of earth / mass of humans ratio, and i am too lazy to calculate the possible approach to unity, adjusting for decrease in the % growth (my guess is that the earth at 6x10**24kg is well ahead of the 6 billion people, even at 100kg each = 6x10**11kg -- note: not adjusting the mass of earth for the mass of people ;-)).
--ravi