As a currency it is just as trustworthy as any other imaginary money system. It's value is highly speculative, like the NYSE. Nobody really trusts the NYSE just as you shouldn't trust the value of BitCoin.
And this is basically the sad thing about the economy. Stock used to represent real value that a business had: The ground it stood on, the buildings it owned, it's warehouse stock, it's patents, the knowledge of the people working for it.
That has all changed into how much another fool will pay for it. If you look at the net-bubble of 2001, ISPs were being valued based on the number of subscribers to their service, times an imaginary amounts that investors though those subscriptions should be worth. However, it was never really backed by anything, other than some hope that another sucker would buy their calculation and be willing to pay even more for the same stock.
It would be nice if stocks could go back to what they were for: Investors believing in a company and supporting it by trading a percentage of that company's capital for an injection of money. Not like gambling in a casino or with art where you hope some other sucker is willing to pay more for imaginary value in the future than you did. Also my problem with intellectual property, it's usually based on imagined value, instead of actual proven value.