Saw it today on IMAX, I had a great time and don't really see what everyone is complaining about.
Was it perfect? No. But I wasn't expecting perfection.
One thing that's always been interesting for me with DC, is that DC tends to take itself pretty seriously. Whether that's Batman, Constantine, etc. Where Marvel seems to be having a grand old time having the Hulk punch Thor out of the screen, Batman V Superman seemed super serious.
I wonder if that's a conscious decision they've made.
Personally, I'm glad they killed Supes off for the time being. He's so overpowered that it's nearly impossible face any realistic conflict when he's around, unless you want to bring Kryptonite (or magic, I guess) into every damn story line.