It appears that some number of userpics may have been lost. We had a disk failure though we did not expect to have any userpic loss as they are supposed to be replicated over several disks. However we have received a report of a user who has lost some userpics. We are looking into why they weren't. We are very sorry for the inconvenience that this has caused.
faeries
Pretty much this. He can only do so much about drive failures, like any other computer.