I simply don't think the general public can get used to the virtual currency where a string of characters translates to monetary value.
The distance between a malware/phishing scam is the computer and the bank. Now that you move your money into your computer, stored as a string,
the distance between your money and it getting stolen feels a lot smaller. Hence the trust issue.
People really have issues with the trusting part of the bitcoin this is without doubts true, the bitcoin also simply has a bad name due to the media that only told some bad stories about it..
The thing is trust now can be gained simply by being there for a long time. Look at paypal, that is an exame of just beiing there for quite some time. Although their fees are hugh people still use it.