Its' a bit too early to answer for sure, but I'm betting the last-minute date change probably wasn't a wise one. According to sources, including the $3.3 million picked up during evening/midnight shows, Star Trek into Darkness only managed $13.4 million on Thursday, which is plenty of reason to cause for panic. However, many fans probably weren't aware of the last-minute date change. Still though, its' starting to look unlikely that the latest Trek reaches the century mark for the four-day period.
Right now, comparing recent Thursday trajectories, Trek will probably earn in the $25 million range on Friday. Unless that changes, the four-day start now may only be $85 million, which would be disappointing if that were the case. In order to be considered a successful debut, Darkness needs to clear $90 million for the period (based on the huge buzz its' had though, it really should be debuting to north of $100 million).
Audiences that saw Darkness loved it, giving it an "A" CinemaScore, which may help word-of-mouth in case the debut turns out to be somewhat disappointing.
