I'm going to make it clear that I havent finished the series and I do intend to soon. You can read anywhere online about that the show is about so I will just point out some of the issues with the anime from a fair perspective.
The show has a good premise about living in a game world and if you die in it you die in real life but as you watch you will realize that this premise is of very little and eventually to no use later in the series which part of its downfall. The show intrigued me and I wanted to watch it of that vaguely used premise.
The main problems with the SAO is that it has a severe lack of action. I expected to see some good memorable fights but there is no such thing in the anime. There are fight scenes that involve some pretty bad ass looking bosses but you always get a feeling like you are being jipped on the action. Its not very provoking or intense , seeming as if they are lacking enough detail or sequences and they were rushed or dont exist. For example look at the boss fight they never really showed with kirito on christmas.
The other issue is the series seems rushed. Alot of story lines and character development are lacking. You watch one episode and then the next one they jump forward 2 years (like seriously) alot could have been written into the series to make more powerful arc and sitautions arrive. Overall you feel like this anime is one of wasted potential, not sure how it is rated so high. Overall not a bad anime but suffers from many debilitating issues. I will continue to watch to see if it picks up on some of its intial glory but I doubt.