IMO the manga is still better compared to the anime
I like the manga but I'm not into the drawing style of the manga. I feel the animation really did an outstanding job for pretty okay drawings.
To be honest its like elfen lied, Gore shonen and gore anime in generally do really well even if there not really good. The problem is hardly any gore manga or ln turn into anime and when they do they censored to all hell but doesnt stop its popularity since its always action packed.
AOT is doing so well because a decent gore anime hasnt come out in awhile and none really like to read manga anyway.
That being said its not my favorite anime, since i kinda spoiled myself with the manga already.
I don't think it's a gore.. We had Another last year itself for example.
It's mostly the shounen approach that clicks with the audience. Having a mature shounen with minimal fanservice, lots of action and practically no moe, was refreshing. IMO, it's the most less-stereotype shounen since FMA: Brotherhood.
Oh, and Elfen Lied is a seinen; not shounen.
I'd give it an 8/10 since it's only 8 episodes. That being said, if they keep this level till the 25 episodes, I think I'd generously give it a 9/10.
And as far as if it's everyone new fav. show - well, favorite for some, great for others like me. I love it; though I wished people overhyped it less...
For now, it's the most hyped and anticipated anime of 2013. Luckily, it's almost the best we've got in that first half of 2013. But in terms of quality, we might get something better by the end of 2013. Though, it'll probably end up as the most popular anime of 2013. It's nothing really new - each year, one anime really rocks hypes/popularity charts and this year, it's Shingeki no Kyojin.