While they have not formally announced it, BTC-e recently stated to me that they are no longer dealing with US banks or customers.
This would explain the lower price of BTC on that exchange as USD would be relatively more scarce there.
The prices there are always lower than those on the other exchanges. It's sort of like a hub for all those who day trade when large swings are happening.
Traders there just mimic the buy and sell waves of btcchina and okcoin, so it's not hard to earn a buck there trading.
In regards to US banks, there's a bunch of people complaining about funds not being credited from western banks, so the news are not a surprise really.