This show has gotten some well-deserved hype, because it certainly looks great, and the soundtrack is nice. On top of that, it has a premise that in the beginning, looks very very interesting.
Where this show falls down for me is that the plot is completely and utterly inconsequential.
The problem is that the show tries to head with an episodic format, while not realizing that in many successful episodic shows such as Nichijou or Working!!, the plot of each episode is removed from the others, but they focus on one group of characters.
In Sword Art Online, we see the adventures of Kirito, boy forced into a death game, ala .hack, only he isn't alone here, 9999 other players are trapped with him. The thing is, the story has never focused on Kirito. Each episode, without fail, they introduce a new character we have not seen before, with their own story, and rest assured, you will likely never see them again after that episode.
Even with this format, I thought the show could have worked if it had focused on Kirito, but the show changes focus to the new person and characterizes them for an episode before they drop off the face of the earth.
In all, the only reccuring characters are cardboard cutouts, and all other characters have no consequence beyond their episode.
Although I feel a show does not have to have a good story to engage me, this show focuses entirely on the story, badly told, rather than on other aspects, like action. By the last episode I watched at time of writing, the action scenes had been pared down to about 20 seconds per episode.
To sum up, The show has terrible storytelling, excellent visuals, almost no action, and completely unrelateable characters. Watch it for the pretty visuals and decent soundtrack, then forget about this empty show.