This may be old news to all of you by now, but I just feel like putting this bit of information here. It seems that only a few months after Disney made that announcement which the OP talked about, they all the sudden changed their minds and decided to get rid of all of the EU altogether and deemed it non-canon in order to create a new EU. They then relabeled all of the old EU stuff under the name "Legends", which too me just seems like a polite way of saying non-canon so that the fans wouldn't immediately freak out.
Honestly, I'm not sure how to feel about this. A large part of the EU was sort of garbage, but there were some gems in it that I will be sad to see leave. About half of the stuff in the EU was good in my opinion, but I'll still miss everything from the EU, regardless of whether it was good or not because it greatly expanded what the Star Wars universe could be. I just hope that this new EU will focus on a wide range of things for the new EU and have some variety instead of just being stuck in the Original Trilogy's shadow and only doing EU stories that take place in that era.
This "changing of the guard" if you will, seems to mostly just apply to the post Return of the Jedi EU. The Old Republic era stuff (anything taking place before Episode 1) should still be okay and probably won't be affected too much. I don't see why the Old Republic stuff couldn't still be considered canon. They don't conflict with anything, so in my book, they're still okay and canon to me. I also don't see why Disney would just rewrite all of that lore at this point, which wouldn't really make much sense.
EDIT: I have also learned that one of the things that will be released as part of this new canon will be a book trilogy called Star Wars: Aftermath. This book trilogy is intended to fill in the 30 year gap between Return of the Jedi and the new movie, The Force Awakens and will explain everything that has happened up until that point. That is a rather large gap to fill with only three books, even more so if they are going to disregard and do away with EVERY piece of post Return of the Jedi EU and lore. I think that it would be a good idea if they at least incorporated SOME of the stuff from the post Return of the Jedi EU into the novel trilogy to fill in the gap instead of just completely creating a brand new continuity and timeline from scratch. If they recreated everything from the ground up out of thin air, it could very well turn into a similar situation as with the prequels and the novels will just end up feeling like a really bad fan fiction that someone wrote.