S.A.O to me is an anime that revitalizes a genre, especially since the cyber genre (excluding Accel World) has been more gritty and overly-violent as of lately, this anime was a nice change of pace. However, this is not to say Sword Art Online does not have its flaws, because it does, in major ways.
Story: S.A.O. takes a few elements from other series but adds its own unique flavor to it. However the flavor of the anime turns somewhat bitter during the second arc (ALFHeim online). Kirito, our main protagonist (to me) is a breath of fresh air, simply because he starts off as a powerful character. Personally, when I am watching action anime, I divide the characters up into 2 categories: "Talent vs Fighting Will". Talent being that the character either is already somewhat powerful and/or skilled (Ed from F.M.A, Natsu from Fairy Tail) or comes into being powerful early OR accepting his responsibility on in the series (Ichigo from BLEACH). "Fighting Will" being the opposite which is "getting the crap kicked out of you until your comrade dies or you have a 2-3 episode flash back and magically gaining the power to defeat your enemy" (e.g. Naruto, Luffy, and pretty much 90% of other action anime)
Not to digress, coming back to my point that early on in S.A.O. you see Kirito being the badass, which reading some of the other reviews, people might not necessarily like. Kirito (in episode 2 and later episode 5) is joined by his love interest Asuna, who despite trying to make a female lead, ends up being another cliche damsel in distress. Which irritates me a bit, considering that they reference her as "faster than Kirito" and vice commander of the lead group.
Where the story falls short in my opinion is during transitional episodes. It jumps around a bit, which isn't necessarily confusing but, it lacks substance. The characters just easily accept something (like Kirito's and Asuna's "daughter"). If I were to divide the entire series into 4 parts, part 1, 2, 4 rock! and part 3 is just terrible, with fan service and adding love interests, that just cheapen the show.
Art: Amazing
Sound: The classical music really adds to the fight scenes
Characters: Could have been more developed; especially Kirito
Enjoyment: Excluding "Part 3" I really enjoyed the series
