bitcoin like a fiat currency can be good or bad depends on how it is being used, it can be very good tool if been used to help the needy or the provide the needs of one's family but can be bad if been used to buy drugs and been used to finance those terrorist acts.
Yeah so true u stole my words pal 
As due to its level of anonymity and independency it is to be common. but for good it will be more profitable as due to is liquidity so its very obvious that bitcoin can be used for more goods then bad !