Vantaggi
There is some pretty cool technology that they work with and the employees are, for the most part, friendly. There are some company events and sports teams which allow you to get to know people outside of your immediate team.
The job pay was on par with the industry and the office location (in midtown) is fantastic.
Svantaggi
Knowledge is highly silo-ed with little real collaboration between team members on projects. People are heads-down on most tasks and probably working at cross purposes. Lack of knowledge transfer makes supporting other teams or covering for a team member on vacation difficult.
There's no clear and consistent division of how software or systems are supported ("no one owns it" syndrome for some apps or "the wrong group owns it" for others).
They make heavy use of some home grown scripts for things like configuration management (chef or puppet don't exist) so what you learn there may not transfer well to other jobs.
Development is sometimes done by teams who are not developers...