Hell yes. And don't worry about making it a time sink. Since there's no subscription, there's no obligation to play. Which means you play when you want to play, and not just to "get your money's worth."
There's also plenty of other reasons the game is awesome.
In other MMO's, all players are rivals. Even those in the same faction. If you hit something, you "own" it, and nobody else can get experience or loot from it. This also means if you see someone fighting something, the game mechanics are telling you that helping people isn't the right way to play if you want to get better. If you're in a party, you each have to share the loot and in some games even get less experience. If you see a resource node/quest object, you have to race to it so someone else doesn't take it before you. In Guild Wars 2, everyone is an ally. If someone is in a fight, you can jump and and still get the experience. You each will have your own loot rolls, so no fighting over loot. All resource nodes and quest objectives are instanced for you, so if you, say, find some herbs and harvest them, people can still come up and get their own. If you see someone lighting lamps (or something. Damn near all quests have multiple ways to complete it. From killing things, to collecting things, to lighting things, to feeding things, to helping things, ect. You complete it how YOU want to complete it) for a quest, the lamps are only lit for them, you can still light them and progress the quest. Everyone is you ally, the mechanics are telling you that helping people is the right thing to do. And I love it.
Also what's great about the game, you can level up wherever you want. From the start you can go to any starting area, and level there. And since the game de-levels you when you go into a lower-level zone, there's no high-level players griefing people by killing everything. The mechanics of the game make griefing a very hard thing to do, if not outright impossible. Oh, and when de-leveled, if you fight in a low-level zone, you still get the same amount of experience you would if leveling in a zone equal to your level. This means you're always leveling where you want to level, and not where the game tells you to level. It's also great if a friend just starts. Since you'll be de-leveled, you and him can quest together wherever he wants and it won't be a "sit back while the high level guy kills everything" deal.
And the skills... the game does away with normal skill trees and the whole "tank/healer/DPS" trinity. Everyone has a healing skill. Sure some are better at it than others, but everyone can be that supporting character if they want. And there aren't any skill-trees. Each weapon has its own skill-set and gameplay style. This means you can fight with the weapon you want.
So in Guild Wars 2, you're playing how you want, completing quests how you want, where you want, and don't have to fight other players over quest objects/resource nodes/loot rolls/experience and, well, everything.. It's just... why the hell did it take so long for an MMO to make having other people around a good thing?!
Also, this [http://www.escapistmagazine.com/articles/view/columns/experienced-points/9932-How-Massive-Multiplayer-Should-Work] is a good read.