An online entry from Clive Thompson called: An MMORPG on your back: My latest Slate gaming column. In the article itself, the subtitle says: "Finally, online role-playing games that won't destroy your life."
Is that true? Honestly, I cannot say as I have stopped buying and playing MMORPGs (even strategy games such as Evil Genius take too long for me these days...). I have read and posted stories of people whose partners are playing WoW and CoH obsessively enough, so I will have to leave the judging to you.
By the way: He links to a good Terra Nova entry about playing time.