Further detail on MtGox / Bitcoinica heists

[Inkoin]

Hello,

Would like further detail/clarification on the heists perpetrated against MtGox / Bitcoinica and others.

The success of the heist was due to that users kept current accounts in these websites (i.e. trusted their money in MtGox / Bitcoinica wallets' and these "exchanges" in their accounting wrote it as a liability in favor of "User accounts"/Depositors) and thieves stole these login credentials from the exchanges themselves in order to transfer those Bitcoins to their own wallets?

Would these heists be of a lower probability if users just deposited those bitcoins in the exchanges wallet for purely exchange purposes? I.E. getting fiat government currency in their hands?

These "exchanges" cannot be called as such since they are also deposit takers because they keep that money. They should be qualified as "deposit takers" as well.

Thank you for your replies.

[Ailure]

Yes storing in your own wallet on your computer is safer, as long you make sure to practice basic security and secure your wallet with a passphrase. A wallet stealing trojan can easily steal a unencrypted wallet.

But absolutely safest is cold storage (storing the "wallet" file on a offline storage device). This might be especially preferable with a huge amount of bitcoins that would be devastating to lose.

Keeping any amount of money on exchanges can be convenient for various reasons though (just like keeping a bit of money on Paypal).