I remember playing Runescape for HOURS a day. The best part that WoW has going for it is that it tailors to all ages. Arguably, most MMORPG's do the same, but WoW consistently comes out with all the best aspects first, and they do it right. They know their audience.
But, I do see a decline someday. The giant that is WoW has to have a nerve that will be hit soon. I understand that the economy hit subscription rate. Like lingerie, though, I don't see gaming on a high decline due to the American economy. I'd assume that a studio out there is trying to clone WoW, but improve upon it. How, I don't know.
People often tire of the same routine day in and day out. WoW often feels like a second job, assuming the user has one. With the rise of "support groups" for WoW players, and being that it's already difficult for players to manage their time, perhaps WoW will see a decline in people playing because they have real lives to live. I stopped playing because I realized that there is life outside of WoW.
I also stopped playing Runescape because the population became of middle-school-aged players; immature, date-mongering boys who gave me free stuff and asked for me to cyber-date them. Hated that. It became dull doing the same thing over and over again. Granted, WoW has a much more expansive territory, and more to do than Runescape - I'm generalizing.
Of course, I'm relating to a small amount of people, noted. I understand that WoW is not in the same league as Runescape, Conan, etc.
It will die, eventually. With the coming of 3D gaming, perhaps it will falter, but I don't see WoW having less than one-thousand players on at a time within the next ten years.
