WoW is a great game with very few flaws. If you have enjoyed similar games you will definitley enjoy this.
Gameplay:
This section is going to be split into multiple parts due to the fact that there is different aspects of gameplay for different kinds of players.
Bascis:
You are given 10 of the 12 races to choose from when you start. Half of these races are in the Alliance faction, while the other half is in the Horde faction. The Alliance has Humans, Dwarves, Gnomes, Night Elves, and Draenei. The Horde has Orcs, Trolls, Tauren, Undead, and Blood Elves. Along with the races, you will be able to pick 9 out of the 10 classes. These classes are Warriors (plate-wearing melee fighters), Paladins (holy knights), Priests (casters who can use both holy and shadow magic), Mages (basically wizards), Warlocks (dark casters who can summon and control demons), Hunters (ranged fighters who can tame animals to fight with), Druids (people who can transform into animals such as bears), Rogues (stealth based fighters), and Shamans (People who can use the elements to aide them in battle). Be conscious of your choice of race, different races have different class choices. After creating your character, you can quest, fight, explore, etc. As you progress you gain levels. At level 10 you unlock battlegrouds and at level 15 you unlock dungeons.
PVE:
PVE is player versus enviroment. PVE content is pretty much anything that involves fighting NPCs. At high levels PVE players will be able to do heroic dungeons and raids.
PVP:
PVP is player versus player. This is mainly faction versus faction combat done in battlegrounds, arenas, and in the main game world. However, there are ways to fight people of your own faction. These are duels, which are non-fatal fights where the loser is the first one to be on the verge death, and PVA areas where you can kill or get killed by anyone.
Graphics:
The graphics and anything fancy. Even on the highest graphic setting, the only thing in HD is the Water and other liqiuds. The rest is PS2/Wii quality just less pixelated. On the lower settings it gets worse. Luckily it doesnt look that bad. Also, this mean you run the games on a weak system and won't need a desktop or a new laptop to run it.
Story:
The game has a rich backstory from previous games and novels. There is even more lore introduced in the game. Despite this the game doesn't have a good way of presenting it and about 60% of people hardly know a thing about the lore and could care less.