Its notoriously difficult to buy bitcoins. Most people haven't sent a bank wire ever before, and it feels shady and unneeded. This gives people second-doubts and reduces interest in bitcoins. Makes it some super-complicated way of doing something super-simple.
Yeah this is a problem, here in Australia all I have to do is a "pay anybody" transaction which is easy enough because everyone in Australia knows how to do a "pay anybody". But I can understand how concerning a wire transfer would be if that was the only option.
(Oh and the middle man that I pay to get to Gox takes 4%, which is off putting)
Gox goes down. Bitcoin plunges. There is no easy way to get what the price is, and no guarantee that this is where it will be in 2 minutes. This prevents people from holding it, thus reducing its usefulness.
To hold Bitcoins at this time you need to be a strong hand. So we need more people using Bitcoin instead of holding. Most of the things people buy with Bitcoins can be bought with fiat, so some type of discount by the merchant is needed to get things rolling. Incentives people!
Nobody wants to buy groceries then wait 30 minutes for confirmation that they did.
There will have to be a service layer like BitPay to make buying things with Bitcoin viable (even if it was Bitcoin to Bitcoin, not just Bitcoin to Fiat like BitPay does now)
The thing this service will provide is instant transactions and they would take the risk of a double spend. For a Bitcoin to Bitcoin version of BitPay there would hardly ever be a risk)
This needs to happen because no one will ever wait even a minute to transfer cash at a shop. I used to work in retail. Ignore this one at your peril!
The average joe has no idea what a blockchain is, doesn't like long addresses that look like what CNN likes to show in a green font on a black background before stating the details of Anonymous' latest exploits.
They need to be educated that a Bitcoin is a limited unit that you have responsibility for and its not stored at a bank. Most people don't actually know how the banking system, VISA, paypal actually work either. Don't worry too much about it being too complicated.
Bitcoin needs more integration into already-used internet thingies like Email, facebook, or your normal web-browser.
This would certainly help.
What if Bitcoin is hacked? What if somebody copies their Bitcoins? Bitcoins are illegal. Bitcoins are worthless! What if I accidentally become a libertarian?
This will always be a battle, spreading the truth is the only counter. Never stop spreading the truth. We will have to counter FUD for all times especially with Bitcoin.
Getting people used to protecting their Bitcoins is a important concept, if too many newbies loss massive amounts of wealth due to lost coins and such, then this will create FUD in itself and may become a stigma that will never leave. Education!