Could you not already have BTC in Gox so when you buy on BTC-e or Bitstamp, you immediately sell the same amount of bTC on Gox.  Then the new BTC can be transfered to Gox or just be loaded to gox prior to the next time?  An hour is a long time in BTC, what appeared as a good arb could have diminished greatly if you wait for the BTC to transfer.