Pros
Stability, resume recognition. People are helpful. Very good flexibility to telecommute. Ability to try out different jobs (after good performance and one year on the job.)
Kontras
Bureaucratic, slow, mind-numbing number of processes and people to check off on to do something. Complete irony that the IT systems we use are not connected and far from state of the art to help us do our jobs. Too many chiefs, not enough Indians. No one ever leaves, so little room for advancement. You continually have to re-prove you can do something. No one cares if you did something before IBM, if you didn't do it for IBM, you never did it (attitude.) IBM rates its employees very competitively, but a strong argument can be made that it does not pay them particularly competitively. It has an atrocious record for bringing in new talent, and much prefers to hire from within, so internal positions will goto an IBMer with perhaps much less experience in an area than an outisder. Job movement is mind-numbingly slow. There is no one under the age of 30 in marketing. There's marketing, then there's "marketing at IBM"....and that isn't a compliment.