Pros
Pay is incredibly better than most places, so employees become very loyal to the company. Free food and interesting office environment. Great benefits and perks. Generous parachute package when they terminate you.
Cons
No communication between bloated departments and managers; too many layers of supervision. MIcro-management of time and roles keeps workers feeling oppressed. No recognition for extra effort. Total disconnect between annual review rating and compensation. No matter how hard you work, and no matter how well your annual review goes, compensation and bonus levels have already been decided in advance and seem totally unrelated to performance. Some of the most-clueless workers end up in charge. Talent does not equal growth. We were always told that "Bloomberg is a meritocracy" but many workers end up stuck in the same position for many years.