(As to the term 'gambling', I think people are using the broad definition by which day-trading and other such financial transactions are termed a 'gamble' rather than a 'very risky, poorly informed financial investment on such a short time-scale that one can't possibly make informed predictions of price movement'. Similarly, I believe that poker is often legal because it's a 'game of skill', but that doesn't mean it's not also a gamble.)
I remember reading something in Jack Schwager's Trading Wizards book where someone talked about successful hedge funds not using more than 5-10x leverage.
Leverage doesn't mean much if you don't know the beta (a measure of risk) of the security. I think for most hedge funds the amount of leverage varies wildly based on what's being traded, so it's tough to apply a single rule of thumb to an entire market.
The fishy part is them leaving off bid/ask spreads off the site. Couldn't find them while taking a quick glance.
They also use 400:1 leverage meaning for $25 you can trade $10000. You're wiped out in a 0.25% price move. Looking at the yen today http://finance.yahoo.com/q/bc?s=USDJPY=X&t=1d long or short anyone would be wiped out with that kind of margin.