I felt a little cheated after this build-up when next issue revealed "Gabriel" was just a herald of Galactus. This story gave no hint that was anything but the angel Gabriel in person (so to speak) blowing the horn that means Doomsday. (Armageddon out of here!)
I expected next issue to feature Dr Strange sending the FF to retrieve some mystic scroll or something that would convince Gabriel that he was too early. Then the final page would be an ominous warning that there may not be much time until he comes back.