Warcraft's latest Expanion, Cataclysm!
World of Warcraft (WoW) isn't a bad thing, it's actually an extremely well designed game. Perhaps too well designed. The problem with WoW is that it's too good at doing it's job. As gamers we tend to forget that gaming is a business. Sure we get the occasional title that's a lot more then that, like our Braids, Portals, and Okamis, but over the course of a two year development window the point of the team is to make a game that's going to make the player feel as though their $60 investment was worth it. With a game like WoW and any MMO (Massively Multiplayer Online Game) is that the game has to be worth it's $15 dollar monthly charge. So the developers can't make an experience as narrow or as focused as a typical console game. They have to make a game that's going to drive their customers logging back in every few days. This means they need to make an open-ended game with a lot of content.
Open-ended in the sense that players can choose to play it endlessly and always have new content to experience or choose to play it reasonably and still make satisfying/meaningful progress. Basically, both players need to be given rewards to justify their specific degree of time investment. WoW seems to strike this balance perfectly since their audience seems to play it year around regardless of their level of addiction.
Cataclysm came out on the 7th and it's brought about new races, new classes, increased the game's level cap, and added a ton of new reasons to log in. For a lot of previous WoW players, they're going to want to log back in just to see how the world's changed. Now whether or not they get re-addicted is another thing. While arcade games had to strike the balance of being difficult enough to make players lose quarters, it had to reward achievement enough to pull another token from your pocket.
As sad as it is to know that people are having legitimate problems with WoW addictions, (check out www.WoWDetox.com if you don't know what I mean) it's also quite an achievement on Blizzards end that they can make such a compelling game and maintain it for over 6 years.
If you'll be logging in for Cataclysm, let us know and tell us what is about WoW that keeps you coming back.