The number of "double spends" (most of which I believe is mutated transactions) for the last 24 hours:
2014-02-11 16960
(will edit OP to reflect this)

It is slightly lower than I anticipated, as it was already above 16k 9 hours before the CET day ended (24 hours). Maybe the attack subsided, or someone is having a break.

this is probably related to the current malleability attack on the bitcoin network (25% of transactions were affected today). it has nothing to do with your theft.