Pros
Wealth of information, working with key customers makes just about anything possible because of simply the brute force of the IBM Executive Smash™ or a well-written business case. Individuals are good people and knowledgeable. Lots of potential for mobility, but it's generally not self-directed. Need to move somewhere? IBM has an office there, or you can work from home.
Cons
I don't know how this company survives, given its day-to-day operations. Its email system is atrocious, crashing frequently across multiple platforms and delaying inbound email 10-15 minutes. The officially sanctioned office suite software is very outdated - the new versions of the software from which it is derived are miles better. Its timekeeping system has so many layers of red tape and is so user-unfriendly that anyone who has to use it loathes it. Those who track time often track it through other programs or on paper and transfer the time to the system at week's end. Everything is self-service. Need something from HR? There's not really anyone to ask, or if you do ask, it may be days before you get a response. That response will usually be a reminder to search first. Intranet search is terrible, too, so actually finding what you want is difficult. Need something from IT? What IT? Buy it yourself on the company goods store and hope that it gets approved. Don't even ask for a second monitor or backup hard drive. Keyboards are a little easier to come by, but still difficult to get. Apparently yearly or bi-yearly layoffs. Changes in 401k match payouts and/or annual raise dates in order to avoid having to pay people who are laid off. Technically, when traveling, IBM won't pay for your lunch. You'll get a per diem for breakfast and dinner, as long as you start before a certain time and end working after a certain time.