I'm a poker player who's interested in trading. I've worked my way up from .25/.50 limit hold 'em to be a decent winner up through 30/60 limit hold 'em. I've played somewhere between 400,000 and 450,000 hands of limit hold 'em alone, with another ~15-20,000 of various other games, namely pot limit omaha and no limit hold 'em.
Fundamentally, I think trading and poker are very similar: they're both rather singular endeavors (while a lot of people learn/discuss with others, it still comes down to you as an individual) that require a very strong sense of discipline and confidence. But, that sense of confidence has to be tempered, as ego has crushed many a dream. Above all else, they place a very high premium on mental fortitude.
In practice, I think poker is a lot easier to get a basic grasp of, especially now. There's a couple books that will allow for a strong enough rote strategy to allow the disciplined player to get off on the right foot. It's also easier to take baby steps, since you can move up in stakes very gradually, while never really risking a sizable amount. Will these outlines turn you into a world-class player? Not even close. But, they'll lay a foundation to think about the game, and allow you to make a couple bucks in the process.
I know I'm a winning poker player, but I have no idea if my foray into trading will be worthwhile. However, I do think my poker background will make things a bit easier, primarily in the sense that I'm quite used to dealing with (and rebounding from ) losses, and also the day-to-day grind of variance.