Probably Bitcoin will be replaced in the future. However, because it has become a great herald for the virtual currency system, it is difficult to replace it soon enough. Besides, it almost dominates the currency market so changing it takes a long process. However I still expect a revolution to change it though knowing it will make the market confused.
Well, I don't think bitcoin will replace by other crypto. As we all know bitcoin is the dominant crypto currency which almost all altcoins rely on its value. Though, there are times bitcoin will down but after a couple of days or even weeks it will recover. Soon, in the future those who hold their shares of bitcoin for a long time definitely can have a good amount of profit.