It's an amazing game for old school MMO sandbox games.
Exploration is huge. It just keeps getting bigger and bigger. The desert map at end game is extremely interesting in that you can't see where you are, and have to follow the sun and pay attention to the terrain to see where you are going. Not to mention the water and tea you have to keep on you to keep from dehydration. Much more immersive and realistic.
Hundreds and hundreds of types of enemies. This game is all about killing monsters. And the difficulty level is as much as you want it to be. You can breeze through killing lowby badies, or challenge yourself with skull level beasts many levels above you. And the gear they drop isn't level restricted so you can use whatever drops if it's better than what you have.
The fighting animations are extremely smooth and addictive. Some of the best visually pleasing combat in an MMO hands down. That and the character creator is really what keeps players coming back for hours and hours.
Swapping weapons and Armor between characters is possible. It's a very satisfying mechanic, since you only have to upgrade one set of armor and you can pass it on to your other characters if you feel like a change in class. A few weapons are interchangeable too, which is nice.
PvP is mostly absent at low levels, and severely punished for ganking purposes with very interesting mechanics. You get sent to prison out in the middle of the desert if you gank enough, and you have to try and escape. And there is an entire town dedicated to the gankers in the middle of no where. It's enough to keep it from happening for sure, even at high levels.
Leveling and upgrades make significant difference in power. At 56 your awakening is unlocked and you follow a quest line to gain an entire new set of skills. Kind of like a reset for each class at level 56. It's kind of amazing and feels awesome an powerful for each class.
They update the game fairly continuously. New classes and areas to explore keep coming.
This isn't the 'dungeon and raid boss' MMO, that's for sure, though there are world bosses and group scrolls that summon bosses that are quite difficult but have rewarding loot drops.
Also if your looking for story driven quests, this isn't the MMO. The story is lackluster at best, and quests give very little xp.
This MMO is for the sandbox loving types, kind of like a combat driven hi res Minecraft. You just get on there to decide what you want to do, and you can do it with as many of your friends as you want. The building, crafting, farming, economy, marketplace, exploration, combat, and end game pvp elements are EXTREMELY deep.
Or you can just get on and kill some monsters and try to level up a little more from time to time. Getting to 60+ is a mammoth achievement. But it rewards you with power for doing so.
My only fear is it will run like shit on my ancient i5-3470 