Who's Denis Dyack? He's the outspoken president of Silicon Knights, a company that just finished many years (almost 10, some say) of making a game called Too Human that disappointed widely. And that, of course, qualifies him to be an expert in MMO design, right?
Maybe not, but he's going to call out WoW anyway. In an interview with Videogaming 24/7, he claims that while he enjoyed World of Warcraft, EVE Online was for him personally the better game. He claims EVE has more depth than WoW, and is "a lot harder core." And he says that both games made him force himself to stop playing -- apparently they both just took too much time to play.
We've played both as well, and EVE certainly is a very deep and complex game (almost too complex for many players' tastes, we'd guess). But we'll leave the question of which game is actually better up to you. We will, however, point out that while lots of people have opinions about which games are best, not all of them are developers. If you have strong opinions about which games to play and not to play, shouldn't you be making even better games than the ones you don't like?