I have yet to really enjoy a Blizzard title, but I do own a fair few. One of the main things that blizzard do, other than alot of market research, they actually have never really pushed the bounderies in terms of graphics, or animation, nor gameplay. They actually keep things very simple from a technology point of view, this means they can spend more time with the game, getting the gameplay better for fans.
I would still say that the games produced by blizzard are more akin to fast food, because like fast food it's addictive, and they're usually bad for you, anyone who's been addicted to WOW should know that much.