all players trapped in the world and unable to log out similar to what happens in GU.. However, unlike GU where dying would only make you fall into a coma, in SAO you actually die.
Like in .hack, there are PKs and people aiming to stop them; however, unlike .hack, PKing and stopping PKs is a matter of life and death where failure to stop the PKs will literally result in countless deaths.

Pretty much anything can kill you. Other players, people outside trying to remove the gear from you, monsters, and there is even a story arc revolving around PKs managing to circumvent the towns' anti-pk protection.

Looks can be deceiving. The first episode the Sword Art Online presented us with an interesting protagonist, and a well paced plot. It really did look good. That's where most of the fun ends. SAO is perhaps the most over-hyped series of the Summer 2012 season.

SAO had a pretty good start. The first episode draws you right into the world. SAO follows the story of 10,000 players trapped in a virtual death game. They must clear the game to escape, and death in the game means death in real life. They have 100 floors to clear. An interesting premise. This could have been great, but goes downhill pretty quickly. We are introduced to blob-that-doesn't-matter 1, 2, 3, and so on. Then the 2 Gods of the game who everyone loves.

Kirito is basically the god of SAO. He is one of the strongest players, no, he is the strongest player, a solo beater (beta-tester, combined with cheater. This is usually used in an offensive manner) who has one of the highest levels. Our supporting characters that we are introduced to in each episode have interesting ideas, but usually end up as oh-noes-I'm-in-trouble-Kirito-saved-me-so-he's-the-best-guy-ever. And of course, we have no idea why Kirito is so badass, why he's so strong and powerful and why everyone loves him despite his cardboard cutout character. Oh, wait. It's because BECAUSE WE SAY SO.

He is basically the Deus ex Machina that solves everyone's problems. Everyone loves him. And all the girls love him because of his selfless and noble character. Pffft. And by all the girls, that includes his sister. His freaking sister. And if someone doesn't like him, it's because they're a freaking scumbag that everyone else hates anyways. It's not like it could possibly be Kirito's fault!

And if having one Mary Sue isn't enough, we get 2. Two, I say. In the form of Asuna. She's strong, beautiful, and tsundere. Perfect in every possible way,every male player wants to her virtual sex with her, and if that's not bad enough, our two Mary Sues end up deeply in love, because of a mayonnaise sandwich. Her character is horribly inconsistent, she goes from a bitchy tsundere to a useless moeblob faster than you can say 'Awwwww'. Boring and predictable, despite her unpredictability. The worst kind of character.

Another of one of my main issues is the world itself. An MMO replacing reality is a great concept, however, SAO butchers it. First off, the world is not properly described, we have no idea of the limitations of the system. For the most part, it feels like the writer's making up stuff as he goes along. Also, realism. Realism is important. Get some.

I can somewhat understand why this is so damned popular, though. SAO is written like, well, a fanficition.

You know those fanfic that appear right after a major plot development like the MCs speaking to each other or a character dying? Y'know, those fanfics that basically bring the dead back to life and make the MCs get married? Those sex scenes described with a disturbing amount of detail? Those things that never happen in a decent anime because it's clichéd and just plain stupid? Those sex scenes described with a disturbing amount of detail? Well in SAO, all those wonderful, wonderful events that never become canon because they're just so stupid, are canon.

If SAO can do anything, it can pander to the fanbase. And apparently, these days, an anime doesn't have to be good to be popular. God, all it has to do is pander to some pathetic otaku fantasies, and bam, you've got yourself a cash cow.

However, I'm sensing some pacing issues to come. SAO is slated to be a 25 episode anime. Now, we've had 7 episodes wasted on side-stories that are simply there to establish how awesome Kirito is. I'm going to assume that the ALO arc is going to be animated, since Kirito's sister has a role in the anime adaptation.

So basically, this leaves us 18 episodes for Kirito to clear SAO and rescue Asuna from the clutches of her evil fiancé who is horribly one-sided and only presented as an evil person, develop the romantic feelings that Kirito's sister/cousin is feeling for him, and to have all his SAO friends play ALO with him. All in 18 episodes