The major obstacle I see is adoption, which is hindered by security and non user-friendliness. Many newbies are losing their coins and that’s not good for the network in the long run although it increases the price of bitcoin in circulation. Another thing I would like to bring on board is government’s approach toward bitcoin. If we could not do something to prevent it from being criminal’s currency then not only governments but also rest of the world will have a poor point of view towards us. We can always deal with small issues like price fall (just like current one) as we have dealt with it before this.