I buy every Blizzard game and enjoy myself thoroughly with them. True, doing so doesn't exactly break my bank -- but I believe Blizzard puts more emphasis on fun than anyone else in the gaming community.
Their graphics aren't always the most advanced (although they're always flavorful). Their game concepts aren't always revolutionary (although they always nudge the envelope). But their balance, and their fun factor, is better than any other company I've seen.
I played Vampire: the Masquerade for a bit. It quickly became clear, however, that you could win the game by hiding in shadows, commanding other vampires to come toward you, and drinking their blood until they died. It far surpassed other strategies in efficacy, and was really boring (it took about 15 seconds to drain a body completely; during that time, you had nothing to do but watch).
On the other hand, a year after I started playing Starcraft, people were still developing revolutionary new strategies that completely changed how online games occurred. One month, someone would develop a killer strategy for the Zerg; next month, it would be an unbeatable way to play with the Protoss. The game was so well-balanced that people who played obsessively were still finding major new strategies a year after the game's release.
And Starcraft's story was damned near miniseriesworthy. A good miniseries, too.
I trust in Blizzard like I trust in no other company. Not everyone will enjoy them, natch, but I think they're Quality.
Daniel