The big potential problem with bitcoin is that nothing backs it but people's willingness and freedom to use it.
It's a great alternative to fiat money, especially for traders of black-market goods and services, but there are potential threats to it's continued use including restrictive regulations or the advent an alternative currency that is more desirable or somehow backed by tangible value.
In the case of Steemit and Dtube, is it possible for the value of steem to be backed by the value of it's user's content?
Youtube and Facebook advertise on the valuable content produced by their users, and throw a little kick back.
It is my hope that Steemit becomes a platform that allows users to choose to sell advertising. And that the only way to do this is to sell advertising space in exchange for steem currency.
If this is done, not only will the value of it's user's productive efforts will be rewarded with steem, but that steem will have a very real, good-as-gold, tangible value as the only means to purchase advertising space on the Steemit platform. And then steem won't just be cryptocurrency, it will be cryptomoney. Real money!