IBM has a great upside, but also fosters an unproductive environment of mass paranoia in the base US workforce.
Pros
Large companies like IBM provide innumerable opportunities for career advancement and personal growth. I'm happy with my compensation and I feel like IBM has good systems in place for employee feedback and review processes. Also, I feel work/life balance is effective at IBM. As less staff is asked to do more, management does appear more flexible on where and when that work is accomplished.
Cons
IBM is clearly extremely committed to moving all new staffing overseas to cheaper labor markets. It makes being a US employee frustrating and causes continual staff paranoia. US staff members are rarely replaced, and the existing US workforce is continually forced to do more with less. Resource actions (forced headcount reductions) and department offshoring plans are constantly in progress, and it causes a constant unproductive rumor mill effect across all organizations.