... if you want a social life... or any kind of life... at all!
Seriously, I do not think I've been this hooked to a game since the release of WoW, right the way through TBC and most of WotLK.
Honest word of warning though if you do decide to check it out, be prepared for some serious grinding and possibly spending money in the cash shop. You don't HAVE to, but there's a couple of things that make the grind a little bit nicer (pets that loot for you, for example).
Aside from the grind and cash shop, what can you do? Here is a non-exhaustive list:
Quests - Black Spirit (part of the story line), Story, Town, Exploration, Trade, Production and Repeatable
Gathering - Mining, Butchering, Skinning, Sapping (extracting sap from trees), Hoeing (did I just make up a word?), Logging and Bottling
Cooking
Alchemy
Training - To do with horses, the more you ride them, the better they get
Fishing - Fishing can be done whilst AFK, clear your bags, equip your fishing rod, find a spot and hit space, you can even exit the game (kind of, it still runs but in the background and stop using the GPU so saves a bit of power, great for sleeping and at work)
Hunting - Haven't got this yet, but has something to do with whale hunting for rare drops
Trading - Very big part of the game, has a whole eco-system based around traders in different towns, wagons you can make/buy to transport goods between towns, and prices vary depending on the time of day and distance from where you purchased it
Farming - Find a nice area, plop down a fence and grow some crops
You can also increase your skills like breathing (by running/sprinting, increases stamina), strength (by carrying heavy trade packs, increases weight limit) and health (by eating, increases HP). Then there's crafting, which ties in nicely to a massive housing system. You can own multiple houses in multiple cities, each one dedicated to increasing the amount of workers you can hire, storage space in the warehouse in each town or residences for yourself, or you can set them to use for certain crafting choices and put workers in them to make things for you (you cannot craft yourself directly).
An example of some of these things working together would be beer production. As your workers do stuff for you, they drain energy, and beer increases that energy. So set a worker to farm potatoes (easily done at the first town), grab the potatoes from the warehouse, grab a few more ingredients from local vendors (water, sugar and leavening agent, which I think is a poor translation for yeast), run to a residence, plop down your cooking utensil and chuck all the ingredients in (exactly the right amounts, don't worry there's a wealth of information in the game as well as outside containing this, and much more) and start cooking. You'll end up with plenty of beer which you can feed to your workers to recover their energy, and get them farming/gathering many other items for you (food, crafting materials, alchemy components, etc). You can then make stuff to sell on the marketplace, use in houses, or trade with between towns.
There's so much more to do... breed horses, gain knowledge of almost everything in game and use it gain access to more content, PvP (guild vs guild and open world above level 45), join guilds and partake in guild quests, get paid by guilds, enhance equipment and weapons... I think I have run out of what I know so far, and I'm only level 24 despite playing non-stop for about 2 weeks! Do that in WoW and you would be level 100 with an ilvl over 9000!
I am on EU Jordine, hit me up if you're playing or want to play.