Video game research firm DFC Intelligence has forecast that PlayStation 4 and Xbox One will sell each 100 million units, which would mark the first time two competing systems hit that milestone. Nintendo's Wii console was the only last-generation console to surpass 100 million units sold.

According to Games Industry International, DFC Intelligence predicted worldwide game revenue will hit $77 billion in 2014. Worldwide game revenue was $68 billion in 2013. The firm claimed "major growth" will occur among the core gaming audience and that the industry will likely approach $96 billion by 2018.

Because core gamers are "spending more than ever", DFC Intelligence said the PlayStation 4 and Xbox One could both hit 100 million units sold by 2020. However, price and strength in Europe will give the PlayStation 4 a slight edge, helping it to become a lead platform for Western and Japanese developers and publishers, DFC Intelligence said.

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Keep in mind that forecasts, especially ones looking six years in advance, are susceptible to many potential kinks. For instance, a rival such as Amazon, Apple or Nintendo could launch a new system and completely dethrone Sony and Microsoft from their top spots. That said, because of this probability, DFC Intelligence claimed it was "conservative" with estimates.

As for gaming trends you can expect to see in the coming years, DFC Intelligence guessed the traditional genre of shooters will reign supreme and that the virtual add-on market will continue to grow. DFC Intelligence also said sports would be an interesting category to watch, because it always needs to be updated.