"Fox will get Disney's branding power behind some of its biggest entertainment properties, most notably Marvel's X-Men and Fantastic Four character rosters. Now Disney finally gets to complete its two major geek culture franchises, by adding the X-Men and Fantastic Four properties to its Marvel Cinematic Universe, as well as gaining possession of the original theatrical versions of Star Wars, before the digitally remastered versions of were put out by George Lucas.
Disney will also gain a much larger library of titles and wider distribution network, thereby strengthening the company's position as it moves to launch a streaming service to complete with Netflix in 2019." - Comicbook.com
We may finally get to see major events on screen in the MCU like Secret Wars, a proper Civil War revisit, X-men VS Avengers, etc. The possibilities for the Marvel Cinematic Universe is endless. It will be interesting to see how this will effect Marvel and Sony's decision to make the Venom-Verse movies seperate from the MCU or if they will work out a new deal together to make the entire Marvel universe under one big happy cinematic universe!
Does this mean we can has Groot in Episode IX?