This ^
Is why I liked Guildwars 1, I could play and take breaks unlike WoW when I played that I had to get the most out of that one month fee being tied to the game. I probably will never play a SUB game again, I like what they are doing with Guildwars 2 and it is easily the best MMO made to date.
Unfortunately as much as I love Guild Wars 1, until it's been released and had a few months to stretch out, you can't really say it's the best MMO made. Going on beta footage and perhaps a short time to try it really doesn't show a thing. Only potential at the moment.
It's important to remember that with pretty much every MMO release there are people saying and thinking it's the best MMO made and then it turns out to be kinda *****.