Market Cap Comparisons:
[ ... ]
As others have pointed out, "market cap" is not very meaningful for a "stock" whose price is entirely speculative and which has large hoards that were bought by minuscule prices.
If I start a StolfiCoin with 1 trillion pre-mined coins, and manage to sell ONE coin to a kid for ONE dollar, my market cap will immediately be 1 trillion dollars.
A more useful measure (but wrong in the opposite sense) would be the amount invested: the sum, over every coin or fraction thereof, of the USD amount paid in the LAST transaction of that coin or fraction. Satoshi's coins, fr example, would contribute zero to this sum. For bitcoin, I suspect that this number will be well below 1 billion USD.
Another measure, would be: if all the current owners decided to auction all their bitcoins -- say, within the space of a month -- to the people who do not own any bitcoins now, how much money would they get,?
someone delete a thread from the last page? 
