Anyone paying attention should know that the Thrawn Trilogy hasn't been a real option for well over a decade now. For one thing, the books feature Luke, Han and Leia. Mark Hamill, Harrison Ford, and Carrie Fisher are simply too old to reprise those roles, and no sane person would want to see other actors in them, at least not in the role of Han Solo.
Speculation is now rampant that the movie will somehow "fill in the gaps" left by the Thrawn Trilogy. I'm afraid there are going to be a lot of fans of the expanded universe up for a great deal of disappointment. Disney isn't going to pay any attention to the Thrawn Trilogy when they make Episode VII, and here's why:
Disney isn't going to make the mistake of trying to introduce story elements that don't actually take place on screen. They are going to create an original story that references the previous movies, and that's it. They won't go out of their way to destroy expanded universe canon, but they will make no special effort to avoid doing so either, because that would get in the way of making the best movie possible.