Pros
Fidelity has a good brand and most of the employees are smart and want to do the right thing. It is nice that it is a private company with huge wallets which allows them to invest when the market (stock or job) is down. Good place to work out of school and get some good experience by moving around and trying different roles. There is also a student debt benefit which is good for anybody that can leverage it. Due to their volumes, they will continue to make lots of money.
Cons
They have flattened the organization as part of the "agile transformation" and expect you to make lots of lateral moves (forget climbing the ladder unless you are very junior). They have pushed out most of the good senior level leaders or bought them out via VBO. They are catering to young workers who they can pay less and shuffle from one group to another. Leadership is not engaging or inspiring.