It's gonna open well of course. Anywhere from $140 to $180 US and probably another $50 to $60 ROW (millions). Adding Batman, following the peak of Deadpool as next in that genre and lure of Batman fighting Superman is enough for a good opening even if film was 10% on RT and an mitigated piece of shit start to finish.
The question is, given it is a fairly joyless, medicine movie in general, how well it continues to play particularly ROW. MYself I think it'll make more than MoS in total but will stop comfortably short of $1 billion. And if that holds true and if the clear feedback is majority of non comic filmgoers didn't like the style of it (which I believe will be the case) I wonder how WB will react?
To make the big bucks comic book films have to pull in punters like me who don't really read comics or know the background. And my current view s BvS is going to register as a dud wth that demographic. The impact of a dud with general audiences is felt with the next instalment when they're forewarned and that's where my attention has already swung.
BvS will make money but it's not going to be viewed warmly in general like many other popular comic book films IMHO and that will have repercussions going forward.
Wonder Woman showed the most joy in the film, and she has her solo coming up after Suicide Squad. Suicide Squad looks like it's going to be a fun ride so those turned off by the 'joylessness' in BvS should be able to come back and check out those DC films.
Also whenever Superman shows himself again he may have gone through a rebirth on his personality after what happens at the end of BvS, so not everything needs to be bleak looking forward.