The social aspect of WoW - though very rewarding - is also the part you have to be most careful with. The central problem (IMHO) is that you can't just pause like with a normal PC game. If you are in a group doing an instance or raid it can take several hours, and they are real people who you don't want to let down and quit on.
What I'm finding useful is to budget my time, letting my wife know that I will be doing an instance, or alternatively letting my guild or pug know that I might not be able to play all the way through.
It's very addictive, but that's not a bad thing in an of itself. That just means it's a lot of fun. I also watch too much TV, and eat too many gummy bears.
Freet
lvl 70 Prot Warrior (Tank)
Arathor