My kids love Guild Wars.
Do you play it? It really is a cool game. They keep adding new areas, and you sure get your money's worth, time wise. How old are your kids? You can always tell when you play with children. I often wonder if parents know how rude their kids are, playing online. Not all of them are like that, but a few sure spoil it for others.
I don't care for the style of game that Guild Wars is, so I don't play it, but I have a friend that does (HEAVILY). He actually bought points off of eBay, the guy "met him" in a certain location, gave him the points, which allowed him to upgrade his armor and weapons. Amazing....