Regardless of how minimal or how great the changes are once the playtest is done and the new core books are released, it's going to be called an "edition" by just about everyone. If not for anything but for ease of communication. Whether it's called the revised edition, anniversary edition, 5.ONE, 5.5, 6e, or something else remains to be seen as the D&D community coalesces into some type of consensus (assuming it does).
It'll be okay, too.
In the meantime, I think WotC's corp speak is there just to try to minimize consumer fear of change (which is inevitable because humans generally hate change, no matter how minimal).
That's okay, too.