Quote from: hdcafe on March 12, 2013, 07:28:42 AM

What if the hijackers replace the blockchain with the fake one? All users will find their wallet empty , the hijackers' wallet full of coins.

To avoid this kind of disaster, innocent users need re-gathering with new version of software.
So it comes the initial question: the BTC community actually need a government to tell users what to do finally.

This question has been asked so many times already...

https://en.bitcoin.it/wiki/Weaknesses#Attacker_has_a_lot_of_computing_power

Please read that! (Or face being ignored)

The hijacker could only delay or DoS bitcoin transactions, and might be able to double spend his bitcoins. That would probably cause a temporary panic on MtGox (which would mean some people would be able to buy a lot of bitcoins).

Your coins would be safe!