From the full tilt poker homepage:
"System Update
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wsj article:
http://online.wsj.com/article/SB1000142405311190410670457658...
Layman explanation: Full Tilt Poker runs a wallet system, the sum all the users money is smaller than what they have in their bank accounts.
The 'Ponzi' element comes from their ability to attract new players at such a high rate that they can pay the withdrawals.
What makes it doubtful that this really is a Ponzi scheme is that - a bank run excepted - they probably would end up not paying out a very large percentage of the money they owed if operations continue, simply because most of the those playing online poker get fleeced incrementally, every dollar placed as a bet has a rake associated with it and that rake could cumulatively be a large percentage of the total money deposited. I don't run an online casino so I have no clue how often a given deposited dollar passes the tables before being withdrawn.
If there was one part here that is sloppy/criminal then that should be that they overpaid their affiliates.
A typical Ponzi scheme does not have affiliates taking a bunch of money of the table.