Well, the graphics haven't improved at all, at last as I saw it from the brief gameplay part. So a HUGE disappointment there. A share few of glitches from a couple of minutes didn't help either.
However, by far, the biggest letdown was the trailer itself. What the hell? You didn't release anything for more than 2 whole freaking years so we could be blown away when the beta is opened, and then you change your tactics? After two years. So basically what you've just said is: "we got it wrong, we should have done what Blizzard have done the entire time".
One comment. RED ENGINE GORED ENGINE GORED ENGINE GORED ENGINE GO You Anet. Am I going to buy it? Maybe. Will it rock? Probably? But it will only be available in two years or even MORE. I'm in the University at the moment, so I got a whole new perspective about things. All of you that consider me a hater; Guild Wars was great, Anet management sucked. Big time.
All the new guys here will probably be like, "What? you have no clue about Anet's inner considerations. They're gods. They can't be wrong. You Are. Yeah, yeah, you are. Ass!".
See you in two years time, I would love to hear your opinion then, if you were still here that is. Can't wait

.
Have fun in the mean time. Sincerely.