This game took my life away from me for two years. It was worth it.
The grind to get to max level is quite a big one, but the game doesn't even start until you reach the maximum level. The leveling process is very fun the first few times through on each faction (Horde and Alliance). Quests range from killing a certain number of monsters, getting drops from monsters, finding items on the ground, finding NPCs, escorting NPCs, beating dungeons, among other things. Guilds are very easy to join, and great friends can be made.
The PvP is very balanced by MMO standards. There is the stealthy rogue, a stealthy high damage melee class. There intellectual mage, which a high-burst longrange damage class. There is the righteous paladin, which can be any of three rolls: a healer, tank, or melee damage dealer. There is the savage warrior, who can be a tank, or a melee damage dealer. There is a hunter, a longrange damage dealer that can have pets. The death knight, which can be a tank or melee damage dealer. There is the lethal warlock, which is a longrange damage class that can either be a burst damage class, or a damage over time(or DOT) damage dealer. There is the shaman, which give huge party boosts to either melee, longrange damage or healers. A shapeshifting druid, that can transform into a bear to be a tank, a panther to be melee damagers, a boomkin(a cross of a moose, owl and bear - I know, wierd) to be a longrange damage dealer (or possibly a healer, depending on how you spend your talent points), and a tree to be a healer. Last but not least is the priest, a healing class. They can produce great strategic combinations in arenas, which are 2v2, 3v3, and 5v5. In addition to specific classes, there are 10 different playable races, all which have unique racial talents, which also provides an interesting twist on PvP.
The PvE is also very in-depth, and, from experience, I know once you get into the high level dungeons and raid them five nights a week, it can be addictive like a drug (I still don't know how I managed to quit...). There are some bosses that are your basic "tank-n-spank" where the tank just has to keep enough threat to hold the monster on him, while healers heal the tank, and DPS(damagers) destroy him as fast as possible. Then there are bosses where you have to know when to stop attacking, or move out of a certain area to avoid death. Then there are the crazy complicated ones that take complete and total perfection to down, and everyone must work together as a team. For example, Kael'thas, at first he summons a 4 bosses one at a time, you have to do special things to kill each one, the first one you have to run from and keep from getting hit while ranged DPS kill him. The next spawn is a tank-n-spank, except he uses a move to make everyone around him run around in circles every so often, so the priests must put a fear-ward on the tank and keep one on at all times. The third is a girl whom a warlock must wear fire resistant gear and keep the threat on her and you must place around her exactly right and not pull her, or all hell breaks lose. Melee can't attack her because everyone must be at a certain distance to avoid her using an area-of-effect spell and killing the raid. Then you get a guy that another tank must tank, and he can make people turn into toys every 4 or so seconds for 60 seconds, and if any tank gets hit, you must stall on killing him until the spell is gone, and melee must be at the edge of his hitbox to avoid his bombs he throws. Then you get to fight a lot of weapons (I think 6), which are all minibosses, at once and they must be killed in a specific order, and the raid of 25 players must all loot them. You have a minute and a half to do all this, and after that... you get to fight all four of the previously described bosses at the same time (really fun)!! After three minutes, Kael'thas spawns, whether you have the bosses and weapons killed or not. He spawns phoenixes, which do an area-of-effect move that massivly damages the raid members, he disorientates everyone around him for 10 seconds every now and then, which someone with the staff you looted off the weapons must stop from it happening to the tank or it's death for everyone, he mind controls your players and melee DPS must hit them with the knife they looted to break the mind control, he spawns a huge fire area-of-effect that hits in 2 seconds or so and usually one-hits you if you don't move out of it, DPS must quickly do huge amounts of damage when he charges a 4 second spell that will one-hit the tank, and interrupt the spell after you do the amount of damage to lower his shield protecting his spell from interruption, among other small things, and then you go into his second form at 50% life. This form a lot of things go away, like the spell that must be interrupted, but you still have to get the phoenixes on a tank, break mind controls, and a couple other things. He lifts you into the air and if you are near a teamate you get hit with a chain-lightning spell that can deal a lot of damage. Once you kill him, it's an amazing feel a huge sense of accomplishment and a great feat of teamwork. There are bosses even harder than Kael'thas, but it's worth every minute of stress and dieing over and over whenever you kill the bosses like these.
Of course, for people who don't want to do hugely complicated things like this, there are small dungeons that are very easy that can be done in an hour, quests to do, money to get, and great friends to make.
As I said, even though World of Warcraft took away my life for two years, I don't regret a second.
