I'm guessing Guild Wars 2 is going to be really good because Anet tend to be quite awesome at listening to the fanbase and it's very obvious looking back on Guild Wars' evolution, so imagine taking all the good things about the original and making them even better.
Few things about it, the level cap is apparently going to be around 100, the world is going to be more open, there will be some sort of world PvP, you can choose species (including Human and Charr) and there WILL be a z-axis, meaning jumping WILL be possible! WoW anyone?

Big thing though, there will still be no monthly fee and instances will still be used but I can imagine something excellent is on it's way next year, I'm glad they're starting over on a brand new game, plenty of opportunities for something very special here.
On the new expansion for the current game: It's not stand alone, you need to have one of the current campaigns, thank God that there's all completely high end content, not all that start simple crap.
Also, hard mode is here yay! I shall now at last start playing Guild Wars again as literally everything can be done over again much harder.