On November 13th, from 2100-2359 GMT players at Betfair were offered a bottomless 10x bonus. Roulette was 20x and blackjack was 50x. Players hit this bonus hard as it basically added 10% payback to most games, 5% on slots and 2% on blackjack. The wager requirement was only on the bonus, not the deposit plus bonus that is standard. No games were excluded. There was no limit to the amount of bonus a player could receive.
Players woke up the next day to find their accounts locked. Some players that had cashed out to their Moneybookers cashouts were reversed. At this point Betfair has been silent while players remain unpaid. When more information is available I will post it. In the meantime someone made this video to make light of the situation: