Poker and FOREX most certainly share many qualities.
First, to make it you need to have an understanding of probablities.
Second, in poker you can tell the amateurs based on their betting patterns, in other words money management. Novices will bet on anything, often employing martingale type bets. Experts will be very selective with their hands, cutting losses very quickly and going for the throat when the odds are in their favor. They have a methodology on deciding when and how much to bet. These aspects are very similar to experts and novices in the trading arena.
Thirdly, the psychological aspect is very similar. Novice poker players make decisions largely based on fear and greed. Experts players and traders have systems and methodologies to keep these 2 emotions at bay.