Pros
The wonderful ambiance of the main campus is almost magical- it's a wonderful setting to work in with great decorations and perks (gym, gourmet cafeteria at great prices, etc). Also the prestige simply working at Blizzard is immense, you pretty much have rock star status while you work there. Free games & swag galore. Working on your favorite games since childhood is a fantasy come true. Great executives and upper management for the most part- they were gamechangers for this entire industry. The junior employees who do all of the actual work there all have a great attitude, are the pick of the barrel, and are truly an asset to the company.
Cons
The ranks of middle management is filled with absolutely the lowest forms of life imaginable- basically all guys who were simply lucky enough to be in the right place and the right time following Blizzard's post-WoW expansion explosion- or they were the buddies of Sr. Management. Most of the have zero management training, no college education, and no leadership qualities whatsoever. Many of them are petty and they crack down on innovation & success from the guys at the bottom of the totem pole to make sure they stay there and don't threaten either themselves or their middle management buddies. To be honest, the multiple grossly incompetent managers in the middle ranks is why I voluntarily left this company. Upper management is actually brilliant and the best in the business... but those guys kind of walk around campus with their heads in the cloud just waiting to cash in on their golden parachutes, and they act like part of some secret society old boy's club, full of inside jokes and stories that nobody else can ever relate to. When these guys moved up to Sr. Management, they all did a completely terrible job at picking out their replacements to take over middle management who are the ones who really drive stuff day to day. There is incredibly slow turnover there because most people love their jobs, and very little room for career growth at Blizzard. Most people actually have to leave the company for a few years just to get Lead/Management experience and then re-apply back to Blizzard Lead positions. Pay is slightly substandard for the industry, Blizzard considers all the free games & perks as part of your salary. I'd rather have a industry standard wage though, to help my rent in the very expensive Irvine, California region.