TL;DR: Skill Trees are going away. All key choices from the trees are going to be baseline depending on your choice of Discipline. You gain points to spend as you level on a pool of 21 Utility Skills. That is where your customization comes in.
Yesterday, BioWare did a live stream which detailed how the new Discipline system worked. It was very nice to see it in action and get an idea about the types of abilities they are adding to the game or making into Utility Skills. The stream is an hour long and can be found below.
Watch live video from SWTOR on Twitch
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