Most of the new footage involves an X-Wing battle that doesn't appear to be against the Death Star but some other kind of Imperial station. In fact, the Death Star isn't much of a presence here which is a good thing. We've seen enough of the "fully armed and operational battle station", and this story is supposed to be how the rebels learn to destroy it, not the actual destroying of it. Again they've done a good job of offering more without revealing too much, although I do wish we had never seen that Kyber Crystal. >sigh<
Otherwise it looks like we're finally going to see the "war" brought to Star Wars when 'Rogue One' arrives on December 18th.