Pros
Nothing, Since joining till date didn't observe a single positive sign. Management always try to protect their seat and will throw you out of IBM irrespective of how you perform. Lot of communication gap with management and HR. PTO's are a joke, if you lick your boss shoe, you will be able to utilize your PTO to the fullest.
Cons
need to lick manager's shoes always to get promotions. Otherwise it's hard to survive. There is no HR system in place to raise concerns on working hours and office premises. Bonus is Joke and HR is invisible. Unrealistic goals to achieve. Management without technical knowledge will decide your future in IBM. All these managers can't survive outside and I see most of the managers working in IBM for 20-30 years. If these is any Zero star, I will give it.