Here's the current state of affairs, as of 4:09 PDT. MtGox is at 116, and has been over 114 for hours. BTC-e is at 108 and has been below 109 for some time as well. Why is no one holding USD and BTC in both places and arbing the heck out of these two markets?

http://i.imgur.com/yGPPEEj.png