Difference in price of BTCUSD between popular marketplaces

[Fredon]

Hi,

I try to figure out what is driving price of Bitcoin and especially why is there such difference in price between hitBtc and others marketplaces. As you can see in bitcoinCharts price is 6.8% higher at hitBtc than the rest of popular marketplaces and I can't believe better liquidity, services or stronger security is the root cause.

Could somebody give me some hint please ? :-)

http://bitcoincharts.com/markets/currency/USD.html