Well, I would definitely like to know where he keeps his wallet and what the password for the encryption is. 
How many coins in total does Satoshi have?
Some say he holds more than 10% of total Bitcoins (not in circulation, but in number).
Did he ever dump?
they said he hold 1-2M at best, he has the greatest amount of coin, after him there was finney
no one know if he ever dump, but i suspect that maybe during the 1200 peak he dumped some, just for test how strong was the adoption
Why he would do that at that time. Why not one year before or one year latter or why not tomorrow? You think he would just know because he invented it that there will be a peak at end of 2013 and sold some at that time. You want to say you believe he is a actually a time traveler and he knew the future?