Pros
Too many specifics to list here, especially without parroting all of the others - outstanding health benefits, discretionary time off (huge for new hires who don't have to wait for years to accumulate time off), morale events, interesting speakers, and the list goes on. The biggest pro is leadership that truly listens to its employee base. In the year I have been here Zillow has stepped up in offering a more aggressive 401k package, top-notch health benefits, more competitive pay scale, option of RSUs vs. options, DTO vs. PTO, and so much more. Every enhanced benefit is in direct response to the collective voice of the personnel. Bottom line - employees are treated as adults and allowed to perform at a high level.
Cons
My position is one of the few still typically still occupied by Boomers in a house full of Millenials, so for those fortunate enough to qualify for a position here later in one's career you better be young at heart to keep up.