I've always thought that World of Warcraft was pretty overrated. I was an avid WoW player from 2005-2009 and I must say it's a lot of time (and money) I wish I could get back. Granted there's been some great additions to the game over the last several years to streamline a lot of the gameplay, but generally, it's a pseudo-fun experience. Grinding out meaningless quests to static NPC's to get an item that is replaced in just a few levels, which are also spent questing for static NPC's to get another item that will then help you quest for another static NPC, over and over.
Modern Wafare 2 is also tips my scale as an overrated title. I'm an absolute junkie for the classic, and in my opinion, the "true" Call of Duty games (CoD, UO and CoD 2). But that's an entire essay that I don't feel like writing at the moment!