Pros
Taking the long view (as someone who has been with the company since the late 90's), I have found my time full of interest, both technical and commercial, full of change and challenges.
The company is vibrant and stimulating, always developing new product to meet an ever-changing market place. It's a great place to be for those who want to see what their particular contribution means to the success of the company, and to become a valued expert in some chosen area.
To be honest I felt compelled to write something to balance and counter some of the negative feedback that has been posted. Clearly there have been people who have not had a good experience, but everyone's journey is their own and will be shaped by who they are as well as who they are working with (I mean to point out that reviews can be unbalanced because they do not indicate how the author was to work with, or their skills, temperament etc.). There is always regret and soul-searching when a poor review is posted, and when comment has been fair I believe the company has learnt from it.
Joining can be tough if it coincides with a time when the relevant department is a bit overloaded, but those that see initial difficulties through find a long-term future.
There's a lot of camaraderie, the departments have a sense of working towards common goals, and there's not a lot of the kind of office politics that can dominate large institutions in particular.
Cons
Commercial pressures can be heavy at times (but that is, after all, the "real world"). Joining can be tough if it coincides with a time when the relevant department is a bit overloaded.