As of this article's posting, Black Bullet holds spot #2 (7.18%) in Richard Eisenbeis' poll about the Best Anime of Spring 2014. Not only that, but the #blackbullet tag over on Twitter is bustling with people talking about how great it is. I don't see it at all.
There's something to be said for liking Black Bullet. It's got a very good quality margin in terms of scripting and animation that isn't something to scoff at, but at the end of the day that isn't its problem.
At the end of the day it comes down to the fact that the show is insanely predicable and we've seen it before. Even past the obvious Attack on Titan parallels (a series that I've recently started hammering on very badly), this is basically like every other shounen show I've watched in recent memory.
It's big on action and it features a peripheral romance plot: like most shounen series. It focuses heavily on an abstract "us vs. them" plot that crosses over with themes of discrimination and distrust: like many shounen series. The main character is chronically misunderstood and carries serious emotional baggage (bonus points for the sidekick having superpowers with discrimination tacked on): just like many shounen series. It's all wrapped around themes of discrimination (that barely makes any sense in hindsight), which I also see pop up in shounen series quite a bit.
Now Black Bullet isn't a shounen show, it's seinen, but you could've fooled me.
That's the problem. It lacks a certain something to differentiate itself from the hordes of shounen series I've been through in the last ten years, and it isn't even a shounen. It's got odd pacing, strange instances of character stupidity, and mixed development for all the characters. All that and more are keeping me from liking the show all that much.
People have called out the show for having an excess of Loli's as a reason to hate it. On that note, I disagree. It's not all that bad and they have been surprisingly quick to subvert any sort of sexualization of the girls in the show. It's not really all that bad and I kinda enjoy this part of the show to an extent (the justification for little girls having superpowers plays into the plot). This is not a reason I dislike this show, I'll let it slide easily.
It's everything else that ends up being the problem. It's an entertaining show and it has a good quality margin, but I won't remember shows because they were "good quality". Instead, I remember them for having a good setting, plot, and a new twist on both that sparks discussions for months to come.
At the end of the day, Black Bullet won't be remembered after this season ends, much like Richard Eisenbeis pointed out in the podcast as a counterpoint for If Her Flag Breaks. It might be good, but if we won't remember it after this season ends, it is not the best anime of the season by any means.