I don't watch animes at all, so I might try to give you one or two valid points concerning the manga, which you may or may not apply to the animated series. Reasons for the massive popularity this series gained are inexistent, I guess. I really can't understand why the huge internet hype around it. That said, it is not a bad manga either. Quite good story, actually, once you pass the first few chapters. The artwork annoys me a little. Not beautifully drawn, but it evolves quite well as time passes and becomes bearable. I guess what holds Shingeki no Kyojin together is the pace in which the story is told. The series of events start to get quite frenetically paced, and it's like you really can't take your eyes off of it. Kinda like a similar feel to a George R. R. Martin book. And the killings are as reasonless as George Martin's ones... xD As the story progresses, things gradually make more sense, and the whole tale becomes more and more intricate and interesting. Pointless violence loses focus in detriment of character growth and plot development. I say, all in all, you should give it an honest, prejudice free, try.