Incredible, but so far, according to ESPN, they have 30 players in:
World Series of Poker to offer $1 million buy-in tournament - ESPN
A specially designed Platinum bracelet for the winner.
$110,000 of each buy-in goes to charity.
I think the top pro's will club together to get into this against the rich businessmen, but each of them will be terrified at playing with $1m on the line!