"Bitcoin Hacked" headlines are like the "Internet crashed" headlines from the 90's that came out every time an AOL mail server was unavailable for more than 20 minutes... Ignorant media reporting about technology they don't understand to an ignorant public that understands even less.
What happened yesterday was that the largest Bitcoin market, MtGox got hit with a Denial of Service attack. A large number of virus-infected computers around the internet were all put to work attempting to access the website at the same time, and that prevented users from being able to log on and buy/sell on that one exchange. As far as I can tell, noone lost their bitcoins, they just couldn't see their account. It is similar to having Bank of America website go down for a few hours and the press reporting "Banks Crash".
When it comes to bitcoin, understand that you can either hold Bitcoin yourself, or hold it in a bank (like Instawallet, MtGox, or BTC-e). If you have large amounts of Bitcoin and you worry about it the same way a Cyproit worries about his bank balance, then seriously consider installing the Bitcoin-Qt client, create a wallet, encrypt the wallet, transfer the coins into that wallet and even consider storing the wallet offline on a flashdrive or something that won't get lost if your computer crashes or is compromised.
A little background...
Bitcoins exist on the internet, but they can only be controlled by the keys in your wallet. If your wallet is ever lost the bitcoins are lost forever, so back it up.
Your wallet has 100 unused keys. As your create addresses and transactions, those keys get used up and new ones get added. This means you should back the wallet up frequently if you do a lot with it.
Finally, if you store bitcoins at an exchange, bank, or mining pool, then they control the coins, and you are trusting them to be honest and keep them safe. It is like keeping money in a bank in the Wild West. It is possible for Jesse James to roll in, rob the bank, and leave you SOL. There is no Bitcoin-FDIC.