Mark (MagicalTux) said during an interview on OnlyOneTV that this was the case, that he backed up the Mt. Gox wallet in these transactions.
I think he could alleviate a lot of our concern if he would just prove that he still has ownership of these funds. This should be pretty easy to prove by publishing a receive address an hour or two in advance of a transfer. Can somebody with full forum access post on the Bitcoin Discussion board asking for Mt. Gox to prove that they're still in possession of the funds in this manner? It should be entirely in their best interest to do so.