Matt Krantz wrote an article for USA Today about why he thinks day trading is gambling.

If you ask these day traders to explain what they're doing, their explanations are usually plausible. And since markets' daily moves are random, there is a chance day traders can make money in the short term. But when they're explaining their "secret" to you, you need to sit back and pay attention and use your reasoning. Keep in mind even some blackjack players may have a lucky night or two, but over time, the odds will catch up with them and reclaim those winnings and then some.

Day trading may be gambling, but you can consistently make money as professionals do with poker or blackjack. Matt is correct that the odds are stacked against us, but that doesn't mean you can't find a way to consistently win. Anyway, everything in life is a gamble because life is random and unpredictable. Each decision in life has its risks and its rewards. In my opinion, long term investing is just as much of a poker game.