Star Wars Episode VII holds the key to the fate of much of the Expanded Universe that has grown from the many non-film stories set in the Star Wars universe. According to the Rumors, much of the story following Return of the Jedi will be different from what has been Chronicles in books and games.
However, while rewatching Clone Wars I have come to realize that much of the Expanded Universe will still stand because it goes back so far, both in real time, and in the Star Wars Universe. Also, with Star Wars Rebels, there is more from the past that could be preserved..
The Expanded Universe began with the first 5 Star Wars novels and the original Marvel comics. Names were given to races, vehicles invented, a society described, and so much more. Many of those things from the original Star Wars novelization, Splinter of the Minds Eye, and the Han Solo Trilogy, have become so embedded that they cannot be shaken lose or rewritten.
A few things were slightly disturbed by the Prequel trilogy, but others were enhanced. Clone wars went even further, including so many things from the expanded universe and adding new things of their own. I think particularly of the speeder bikes that made their debut back in the February 1978 issue of the Marvel comics and Jaxxom, the 6 foot tall green martial arts rabbit. Clone Wars harkened back to that early speeder design and included a dead rabbit in the same uniform. Clone wars even used the Kyber Crystal, though in a completely different form and purpose than it appeared in Splinter of the Minds Eye.
So those predicting the death of the Expanded Universe should take breath and sit back and see what comes. I think much of the later tale woven by the books will be rewritten, but I don't think it will be completely ignored. Too much has already been used and I think only the narrative will suffer.