GW2 is a massive, content-rich MMO, that has a lot of quality-of-life aspects that make it a better game from a player's aspect than most other MMOs. In addition to frequent content updates, there is also a huge patch upcoming that will address crafting and and make it even easier and fun to make your own armor, weapons, etc. A class update, as well as lots of PVP and WvW updates that are designed to make the game more fun to play without dumbing-down how you play.
I wish I had more time to devote to it, but whenever I do, I always feel like I've accomplished something and improved my characters. And the world of Tyria is absolutely huge. No shortage of places to go, things to see, creatures to kill.