Unless THIS thread is the hacker trolling and testing!
LOL I wish, my theory is he had to sell them to some people and this guy was just a screw up who didn't know enough. Theymos needs to get his email and do some digging. It could be a test from the hacker though, I just don't know what to think of it yet.
Your finding is a typical BitMixer transaction. It is now evident that Bitstamp coins were mixed through BitMixer. But, the top and bottom addresses has no link after mixing is done.
Similar example, where BurtW found the same for Klee's stolen coins:
https://bitcointalk.org/index.php?topic=686275.msg7804434#msg7804434