Of all thefts and errors that have occurred with Bitcoin, bc.i holds the #1 spot in theft related issues.
Theft under BTC 1000 doesn't get you into the first 30:
https://bitcointalk.org/index.php?topic=83794.0BC.i is still to small to make it to the list.
This wasn't about number of bitcoins lost, but number of people who lost coins one way or another.
Other then Bc.i who lost coins? I believe they were all returned..