It has happened again one Americas most popular bitcoin exchange Bitfloor ( bitfloor.com ) has been compromised and close to 250k USD or 25k bitcoins has been stolen from the sites servers in an attack which is turning out to be very embarrassing for the owner. The attack came to light after the owner made a forum posting on the popular bitcoin discussion forums bitcointalk.org. In the announcement they have stated what, when and why the site got hacked and what the options are for rebuilding the site. The attack is one of the large heists of bitcons so far and it has come to light that the attack was possible due to an Unencrypted "wallet" being left on a server from an apparent backup. The attack raises many questions and so does the actions of the owner who has shut down the site and seized all operations for now until they figure out what they are going to do which has left some of its users not very happy. 
One thing the bitfloor owner has going for him is he has fully disclosed pretty much all the information related to the attack so that the public can see it from the transaction records The attacker left a IP (178.176.218.157) that traces back to Russia and turned out to be a proxy, no surprise there as attack like these often lead no worthy traces for the victim to follow. > Here are clickable links to the transactions, to save everyone a lot of cutting and pasting… https://blockchain.info/tx/83f3c30dc4fa25afe57b85651b9bbc372e8789d81b08d6966ea81f524e0a02be – 16,120 BTC https://blockchain.info/tx/d5d23a05858236c379d2aa30886b97600506933bc46c6f2aab2e05da85e61ad2 – 1,000 BTC https://blockchain.info/tx/f9d55dc4b8af65e15f856496335a29e2be40f128a7374c75b75529e864579f93 – 6,400 BTC https://blockchain.info/tx/42ea472060118ee5aee801cdedbc4a3403f3708a87340660f766e2669f0afeb0 – 60 BTC https://blockchain.info/tx/358c873892016649ace8e9db4c59f98a6ca8165287ac80e80c52e621f5a26e46 – 498.39 BTC
The bitfloor website is currently offline and there is still no word or possible idea if or when it will be back online follow the story further with the below links. Main discussion forum: https://bitcointalk.org/index.php?topic=105818.0 Attack information forum: https://bitcointalk.org/index.php?topic=105819.0