What's the deal with MMORPGs?

I'm considering writing a book dealing with massively-multi-user online role-playing games (MMORPGs), but I probably shouldn't, because I've never played one. Talk about hubris--that practically makes me a 19th century anthropologist or a corporate journalist in Iraq's "Green Zone."But still, I find the concept fascinating. After all, people immerse themselves in a text/graphic/auditory world with its own laws, property, ethics, aesthetics... this is the old fantasy concept of the reader falling inside of the novel.I've read about women who are called "Warcraft Widows" who've all but lost their husbands not to online porn or to cyber-lovers, but to adventure games such as World of Warcraft. Their husbands may end up spending most of their waking days online inside these adventures, neglecting work, conversation, hobbies and sex. And then there are the people who fall inside The Sims. I can understand falling for a fantasy world, but for one just like ours, with rent and chores? This I just don't grok.So I'm hoping that you folks might be able to enlighten me a bit with your own experiences. Care to share, anyone?