I watched POTC3 yesterday. Maybe I've been too much into TF these days. After watching POTC3, well I have to say that it is still pretty competitive, visual wise at least.
So it's really hard to say how well TF will do. If I saw Tempest19's prediction two days ago, I will definitely jumps out and ready to fight and say things like TF can do at least better then POTC3.
But now, I think it's pretty much unforseeable. How big the base of TF fan is? How many of them hate the movie? How will general audience accept the concept and visual... ? These are all question mark elements...
Of course I cross my fingers for TF to do well, so that we can be certain that there will be sequels coming up. Don't really mind whether it's gonna go into top 3 of box office or something, because from the current leaked footages and trailers, TF is already good enough to me (at least visual wise).