Yeah, Dark Horse did the "one hundred years later thing" already. When Lucas Books decided to close off the NJO era and start the Legacy era, they also decided to do this comic book that jumped ahead a hundred years from where they were in the chronology. Kinda like how TNG started as the TOS movies were still being made. I'm not sure if stories in the "hundred years later" setting are still being written, though.
The only time in either of the trilogies when exact numbers are actually mentioned is AotC, and it made sense because the audience was jumping ten years in just three. Episode VII, on the other hand, will be continuing on from a thirty-two (and a half) year old movie. Whether it's 30 years later or 40, it doesn't need to be brought up in the movie itself.