STID's underperformance can't be rationally explained, there is no true explanation, the marketing was very solid, the trailers were well received. If we're looking for answers, there is maybe the 4 year gap from the last one, maybe people didnt have as much interest, maybe the novelty effect faded away, but it's still going to hit 200 M + domestic, which is still good, even if disappointing.
Overseas is another story, it's on track for 200 M +, not much more, ST 09 did a dismal 126 M overseas, because ST has never been popular overseas, they made efforts to focus on the action aspect with explosions, mass destruction, the jump is still pretty big, but ST will never reach huge numbers worldwide because of this.
Man Of Steel has impeccable marketing, they are just doing everything they can to remove the bitter taste of Superman Returns. Notice how they built up the whole thing, a first teaser catching your attention, "what is this movie?", then the second beautiful trailer teasing some bits, but mostly showing the atmosphere and human aspect of it, and then the third trailer establishing the epic feel of it and just showing you right away that this buries all SH movies.
THEN, the fourth trailer showcasing all the action, and this onslaught of TV spots all showing tiny glimpses of the amazing action there is in the movie.
SR is deemed boring by many, and now, they are showing action all the time, to make sure that you see how it already trumps SR in just a couple of seconds of footage.
MOS is tracking currently btw 100 and 125 million OW domestic, it should explode overseas too. The buzz is just incredibly high, this will be THE event movie of the summer (although Pac Rim is not far

), the movie that everyone is going to see.
Seeing all the footage we've had + the few reactions + the buzz from WB execs (who would shut their mouth if the movie sucked), we're probably getting an incredible movie, and WOM should be pretty high.