SAO really bored me, to be honest. It was extremely straight-forward with hardly any development. It didn't confront the obvious issue of video game addiction/compulsion that is strongly associated with MMOs, it just immediately set them on their path to trying to get out. Then, after the first few episodes, they might as well have thrown out the entire plot and setting and just been a slash-and-hack fighting anime with some weird romance. It didn't feel like they were actually in a game anymore. The main character proceeded to BREAK THE GAME in a dues ex machina to "win". It was way overhyped in my opinion.
Log Horizon focuses more on the addiction aspect, where they don't really consider trying to get out, since they are extremely happy they are now INSIDE their favorite game. They try to learn about the world they are in. And it maintains the feeling that it is actually in a video game, and not just a fantasy fighting anime.
Also, when I saw this:
EmpirezTeam wrote:
"when you die, you're gone forever"
I immediately thought of this:
Made it even better when Zagros mentioned Fate Stay/Night.
the new fate stay/night looks cool too