For the first roughly 2-3 months it's an great and impressive game. Very addictive and fun, and keeps you hooked behind your screen for hours. But after a while when you have your first lvl 60 character, its becoming a bit of a drag all. You realize that the community contains mostly of immature little kids, or really selfish people that confuse the game with real life. Getting some help is mostly very hard to get. Even when you only need a short answer or direction, almost nobody reacts on your question, while there are literally hundreds of people in a city.
I think the main attraction for wow is, how accessible it is, real easy to play. you have this enormous environment to explore, which really was jawdropping for me in the beginning. When you are flying your first windrider is simply astounding. The leveling system is also very great with awesome skills, you can learn. pvp-ing could be very much fun, the only problem is that some people really get off on feeling godlike. so they love running around area's lowlvl to them and annoy the crap out of the opposite faction. But when you get a chance for a fair 1vs1 fight, it's really great and although people might disagree, quite balanced. But most of the time when you are having a fun fight, some idiot from the opposite faction runs into the fight.
The Battlegrounds can be fun too, but it's mostly very unbalanced. I enjoyed raiding dungeons the most. If you have a good guild(and with good i mean fun people)it's really fun to do a guildrun. You make a balanced group, get everyone on teamspeak and raid the hell out of all the bosses, i think i loved that the most.
In the end i still enjoyed the game very much, and it seriously endangered my social life and my education. It's a really great game and when the expansion releases, i will probably turn into an addictive, anti-social compter-geek again, but hell it's worth it. I probably can't give a good opinon about the genre, because i never played any other mmorpg. But if i voted a month ago when i was still playing like madman, it would probably be a 10 but now.