You know, I'm no slouch when it comes to using the Google and such... and while I've seen that quote repeated on many message boards, I've yet to see any attribution to the original article where they're actually quoted saying that.
Here's what the IMDB has to say in it's FAQ:
I searched quite a while trying to find the original interview everyone keeps referring back to; however, I kept getting PMs from people on the boards saying they had read the writer's original/source interview, and that was, in fact, what they said.
So, when all I could find was that huge paragraph I quoted, I went ahead and posted here just to let everyone see what was floating around on the Web.
Truth be known, unless we find the actual trascript of the original/source writer's interview, then you are right--we will really never know if the spell is broken. Or...as stated above, we will have to wait for the DVD and commentaries....
I particularly wanted to know because I thought the same thing about Bootstrap's comments....and Will's response ("Then it depends on that one day."). The green flash of light, IMHO, appears more often than it should if it is signaling only the return of souls from the dead. I think it is signaling moving from one realm to another. (Why else would it flash when Will leaves Elizabeth and the island?)
We ALL want the spell to be broken and for the movie to have a happy ending. I think there is a lot more to this than what is seen on the surface.
For instance, I found an interview on the web with one of the writer's, and in it, he was talking about four clues in the 2nd movie that foreshadow or let the viewer know that Jack is going to die at the end of the movie.
He listed them all out and, yes, looking back, I can see it very clearly, but I don't think I EVER picked them up in the movie itself.
I think the writer's tuck in a lot more than we can ever fully realize. Do a Google search on the two writers, and you will find interviews that show you this.