Pros
Deloitte does provide, at first glimpse, a collegial and familial environment. Externally, it is everything it appears to be - a large well run consulting machine. The majority of staff are intelligent, the company is well organized, staff at Manager level and below are approachable and candid, and the work can be very interesting and challenging.
Cons
On the Organization and Change team there is a lot of gossip, favoritism and cliquish behavior. There is less emphasis on consulting performance as related to client performance than on one's desire to kiss the behinds of the internal "in crowd". There are a lot of politics, a lot of back stabbing and less opportunity for Sr. Consultants and below to defend themselves against potential onslaughts of managerial self interest.