Management, management, management. Oh yes - and bureaucracy rivaling the US Government.
Your experience at IBM is 90% dependent upon how good your first-line manager is....if you have a strong, supportive manager, you'll be happy, but if you have a weak one, you're doomed to be miserable. Luckily, most first-line managers are pretty good, but they have the most thankless job in the entire company because they get it from both sides. Their departments are continually squeezed by upper management, but they are powerless to do anything about it, so they have to hear the complaining from below. Lower management has no REAL control over compensation; it's all determined in the stratosphere of executive management.
Executive management at IBM, in my opinion, has degraded to ABYSMAL. I now truly believe our Senior Management flat-out LIES to us about compensation, job outsourcing, and other difficult issues. Instead of leveling with employees, they spout all sorts of sunny platitudes ("no job added in India or China is eliminating a job in the US") that we all know, from personal experience, are NOT TRUE. IBM has also become far too top-heavy, with far too many VPs running around and very little real control at the lower levels of management. We in product development cannot even travel on business without VP approval!
Many of us now also believe that only those who suck up to Senior Management get the recognition and promotions available in the management ranks (technology promotions seem to be more performance-based and fair). Those who speak truth to power are often not rewarded for it.
Finally, the bureaucracy inherent in an enterprise the size of IBM is frustrating, to say the least. Simple tasks, like acquiring necessary test equipment for our software releases, involve quarter-long review, negotiation, and approval processes that waste time and put programs at risk. *Finance* truly has the control over IBM -- not technology.