Pros
Many employees are allowed to work from home, and even have very flexible work hours. I've never felt micro-managed and can do things as I choose. As a top performer, I've always been treated very well and have been given great opportunities. I've gone to special leadership-training courses and have been supported in many of the initiatives I've started. As such a large corporation, I've been able to work on some of the biggest issues facing IT. Life outside the services organization is generally very positive right now.
Cons
It's huge. The bureaucracy is pretty pitiful at times. In the services industry, since there is such pressure of lowering costs, there is no room for pay raises, bonuses, or even the necessities of the business, such as good hardware. We have to get approval for every little expense. The senior leadership in service delivery (outsourcing) cares very little about "leadership" and entirely "management", so communication in that division is very poor. I could not in good faith recommend someone join IBM in the service-delivery organizations right now. There's alot of challenges in that area, and a dearth of leadership. However, in other divisions, it can be an entirely different experience, and the company as a whole is performing very well. The pay scale can be all over the map, depending on which division you are in. I don't feel like the salary and benefits in service delivery match what I could get elsewhere in the industry as a top performer.