Pros
IBM offers diverse job opportunities due to its size and scope which enables mulitple jobs while staying with the same company. Historically it has attracted smart people looking for this type of single-company career, allowing for extensive long-term personal relationships. If you are selected to be a "high potential individual" then your work assignments will change at a fairly rapid pace and compensation will rise quickly as IBM tries to retain you. (Fall off that list and your career instantly transforms into a job.) Mangement will push you into jobs you are not ready for to test your abilities to cope.
Cons
IBM is cutting expenses in order to drive executive compensation. They are focused on employee expense, by cutting staff and nickle and diming in the US and other developed nations, and moving work to developing nations such as India, China and the rest of the BRIC. This is a rather sad state of affairs, where people are losing their jobs because IBM can find other people in other nations who will do the work for significantly less. In the short term the savings to the company are real. In the long run, the spirt of the company will be lost.