"... growing whisper within the security industry in Melbourne that there weak security might have been breached from China. ..." ~ http://news.ycombinator.com/item?id=4605335
In IT security here in Melbourne, first I've heard of it. Also why would network security specialists need to fly over 30 hours from Europe? We also have some pretty capable teams on the ground here already.
Given the time frame of when it happened it's more likely a change that has been borked in some way with difficulties in rolling back.
No trouble and agreed - rumours flying around like that don't help the problem. If there was that level of security breech, outsiders would probably do more than lock everybody out anyway.
Finding further information about it: looks like a core switch died with the backup not kicking in. 12 hours to work around is a but much though.
Given the time frame of when it happened it's more likely a change that has been borked in some way with difficulties in rolling back.