What's the usage of Bitcoin outside the mainstream of the application such as in black market, gambling and pornographic dealing? I think all the applications above can make sure that the hard currency Bitcoin will not die, however, the true value of it should be shown after it stepping into the mainstream of the application.
Bitcoin's usage has definitely spread to other things - for example I use Bitcoin to pay for a majority of my servers and web solutions - but we're still quite a long way away from reaching the point where you can use Bitcoin to buy anything you need (where fiat is currently).