Pros
IBM is a good company for techies looking to learn on the job. The services organization provides the breadth and depth few service organizations can provide. IBM provides an arsenal of products that are considered the best in the business and used by most fortune 500 companies which opens up the door for advancement outside the organization. Overall it is a very good stepping stone for your career.
Cons
IBM is very HR oriented when it comes to compensating employees. So if you happen to below the market reference point, you have a chance of getting a raise. Even when the company does well as in the past year, the benefits are not passed on to the employees. The raise this year was 0-2% for the IT Specialist job category which is pathetic by any standards.