DuracellEnergizer said:

I loathe the whole notion of "official" canon, so consider me one of those people who aren't pleased with the idea of making the films and the NuEU 110% compatible with one another. Continuity should be an option, not a prerequisite.

And what a weird way to go about it, right?

"Hey, Everyone. Remember 20 years ago when we said this was the official continuation of the story? Well, we're making a new movie now, so any and all of that stuff may or may not be official anymore, sorry. But we're gonna be writing more stuff and starting right this moment it's officially official. We promise."

After re-reading the story on the official site, they are still being unclear (for obvious reasons) as to whether or not Episode VII will actively overwrite the existing EU. They probably just want to get this announcement out of the way now, before they head into main unit photography in a few weeks and story details inevitably leak out.

Like I said, this isn't without precedent. The Clone Wars movie/show is barely compatible with the older clone wars (lowercased) stuff. Maybe instead of making promises they know they can't keep, they're simply saying up front "there is no direct connection between the new material and the old. If old stuff gets contradicted, the new stuff trumps it every time, no retcons."