Pros
Microsoft is at its heart a startup that found itself having grown into a huge company. Every day you come to work, you'll be joining the smartest people in the world. If you like competition, you'll find it here - the system is set up to encourage competition between employees, managers, teams, and groups. Benefits, flex work, and time off are industry leading. Also, the company gives huge amounts of money to nonprofits and should really do more to get credit for all the work they do in this space.
Cons
The competitive nature of the work environment isn't for everyone. Also, benefits are going through a long term redesign which is resulting in a reduction of benefits/increase in costs for employees. Morale is closely tied to product perception and success in the marketplace, and with MS losing its grip on consumers morale has taken a hit.
