I liked it.
SPOILER ALERTS
It was slow and almost jumpy... there is a TON of story to throw in before it all goes down.
Even my boy (11) kept asking, why is he (BM) going to fight Superman. After the flick he was, oh I get it now.
The bad reviews stem from too much artsy hate - it can be slow, there is pretty much ZERO back story on anyone, and gnerds still wanna hate on Affleck at the Bat (whereas I thought he was the 2nd best part of the movie next to WW's scenes- HOT; even her Amazonian music was hot).
Some more of the bad reviews are because Superman dies. Anyone who knows anything knows Doomsday killed SM in the comics and this is mirroring that.
Some of the extreme gnerds don't like it because it shows BM using guns (which he never ever ever does, its his thing) and him killing people. Same people that panned MOS for SM killing Zod at the end. And that don't like SM is in a relationship with Lois and so many people actually know who SM is (which is kinda odd).
This was eons better than MOS; I'm sorry even for me that was a crapper and I like everything.
It is polarizing and creates opinion, good and bad. This creates people talking about it which is a win. They can easily shrug off the critics and say, 'Look, the people have spoken' when you see the box office.
Myself, I completely enjoy the Joss Whedon world we live in, where movie concepts can be re-imagined for new and updated storylines. Hell if Disney can retell/re-imagine Sleeping Beauty, Cinderella and Snow White, why can't DC retell their biggest stories?
I also liked the more hands-on Alfred. Very cool concept.