Vantaggi
All of the best reasons to work at IBM are gone. They used to have great benefits. Management used to care (somewhat) about their employees. I have heard the stories from IBM-ers who worked for IBM starting in the 1960s. All of them say that it's not IBM any more. It is an empty shell of what it used to be. Outsourcing has turned a once-great computer manufacturer into a services-only based business.
Svantaggi
Education is why I left IBM. I was set to take a Masters Degree, and asked my Manager if there would be any time considerations for my education. The manager said 'no.' Now mind you, I had given IBM hours of free overtime to the tune of 18 hour workdays very often in order to fulfill client needs and meet deadlines. The manager was adamant, he absolutely would give me NO TIME CONSIDERATION for a Masters Degree. IBM *used* to brag about how they supported employees' educational pursuits by paying for schooling. PSHAW. They stopped paying for low-class employees' educations in 2001, after 9-11-2001. Then, they stopped paying for Team Leads' education in 2003-2004. They might still pay if you are a manager or Sr. Manager, but now their former boast rings hollow. Anyhow, I quit IBM in order to take my degree and finished in the top of the class. I will only go back to IBM if all other opportunities dry up for me. IBM is like one of the Pyramids in Egypt. There was once greatness there, but all that is left are archaeological ruins. And, the ruins are not great wonders of the world, they are just ruins of a once-great business that had values.