The biggest problem/hurdle for mass adoption of BTC is new user's having to exchange fiat for it. That transaction anchors them in an exchange rate cost and if the value of BTC (to USD for example) goes down they may feel they've lost money and sell the BTC they purchased.
Agreed .....that ease of exchange to/from fiat and a stabilized rate is needed for mass adoption.
Many...very many... are working on this now like
atm's..prepaid bitcoin cards, stabilization funds ,etf's etc and I am 100% sure this will all be achieved in time. We are still in the early stages.
The price at which bitcoin will be stabilized however is likely to be very different from what it is today and therefore we will just need to go through the process including the ups and downs that come with that.
RE wanting to sell if the price goes down..some (few) may do if it is prolonged.....many however will hold in the hope of appreciation to the level or higher than they bought in at so I suggest that is less of a factor.
Mass adoption may be a lot closer than many think..now the big players like bitpay have entered with a target of a 33 fold increase in merchants in 29 months to 1 million..should they get close to that or even surpass it that goes a substantial way to mass adoption
Personally I believe that the ease (and cost) of buying bitcoin for the masses in order to buy from these and other merchants is the hurdle that requires the most attention.
currently if you have currency other than the majors ( $ EUR CNY JPY) the conversion cost is running about 3% that's too high. Worse if you then need to reconvert to another fiat in order to spend. A card which can easily be loaded and reloaded with bitcoin using almost any currency at 1%
or below AND is easily available to the consumer and easily useable almost anywhere will probably be the route to mass adoption and someone will soon provide that.
in fact its already here
http://www.coindesk.com/exchange-anx-launch-reloadable-bitcoin-debit-cards/but they charge 2.5% and there is a currency conversion charge and balance is in $'s so its not quite a true bitcoin card YET
and the prepaid card
https://bitcointalksearch.org/topic/m.8095199which i do not think is rel-oadable YET has a 10% cost ( but they have been asked to reconsider the pricing). This is just a few days old so we WILL get to a reloadable 1% cost sooner than later. At current speed it may even be available within weeks or days
and of course Xapo
http://www.coindesk.com/xapo-bitcoin-debit-card-launch-month/EDIT..I have rechecked current rates for exchange in Philippines..they are already down to 1% as of July 9th This will eventually be the norm ( or lower) for everywhere.
http://www.reddit.com/r/Bitcoin/comments/2a7ze3/we_at_rebitph_have_decided_to_cut_down_our/