A lot of people on the Bitcointalk forums have made educated guesses, the fact is he still works on his business and charges for subscription to his blog, I doubt he has amassed the largest stash of Bitcoins in the world.

"the fact is he still works on his business" a lot of billionnaires still work on their businesses, if not most. This hasn't been the norm of Bitcoin - most people getting rich just went away with the coins, which is pretty bad. His estimation accounts for the assets he owns, same method as for the fiat billionnaires.

For the other question, there is only one pankkake.