Pluspunten
Many options for lateral moves within IBM, unlike at other consulting companies. Work from home is standard for most internal jobs, so it is good for working parents. If you want to work on cutting edge technology and you're smart, then there are opportunities at IBM.
Minpunten
If you're a client-facing consultant, this is probably the worst of the consulting companies to work for - very strict travel policies, no perks, lowish pay. On the other hand, experience has been that compared to PwC, hours expectations while at client site are lower. Also, the PM role at IBM is tons of work with very little opportunity for advancement and very little prestige. No real "partner track" at IBM, so it is pointless to do the grueling PM role, and you don't make a lot of money for it. IBM treats it as almost an administrative role, with Solution Architects or IT architects carrying the higher pay and prestige that the PM role tends to carry in other consulting firms. IBM has a huge bureaucracy. IBM culture is driven by its older (compared to other consulting companies) workforce. Many internal roles are filled with people aged 50+, people who have been with IBM for 20 years. It is not a "fun" place to work. There are no happy hours or work parties. I wouldn't recommend it to people right out of college, especially if they don't want to work from home a lot.