Terry Rossio (screenwriter of potc3) said this;
I suspect that it will probably be there by the time the artwork is done.
he also said this regarding the "at worlds end" or "worlds end" discussions;
When you seen the alternatives side by side in text, WORLDS END is cleaner-looking on a poster and in print. And for some, it invoked the theme of 'end of an era' better; whereas the AT WORLDS END pushed the double-meaning more towards a specific location.
Also it was pointed out that in media ads, the spoken AT WORLDS END might be problematic ... imgaine ... "In other news at world's end, the new installment of the Pirates of the Caribbean franchise ..." ... the 'at' created a possible continuation of line problem.
In the end, though, the counter-arguments prevailed:
1. In fact the world doesn't come to an end, so why promise it?
2. worlds end is essentially dark and downbeat ... what if there is a tragedy in the news that week or month ... who wants to go to a film that invokes it?
3. AWE is better than WE
4. fans have already embraced AWE
5. At Worlds End seems more nautical, less science fiction