I can't speak for others, but for me Guild War's combat is easily a step ahead of WoW.

WoW's best characteristic is lore. They do a great story, and they have a big fan base.

But all the people that I know who have played both Guild Wars and WoW find Guild Wars to be the vastly superior game.

In fact, of the people who don't like Guild Wars that I know, they don't like it simply because it is too challenging. WoW is a graphical chat interface. It requires almost no skill, just like Everquest or Everquest 2. I was in one of the best guilds in Everquest 2 and was included in all high level raid content, and considered one of the "best" healers. But a blind monkey could do what I could do, just like in WoW.