An American Dow 30 icon when I joined. On several 'sell' lists today. A business without beliefs.
Pros
There are many career path opportunities coupled with the ability to build and develop expertise and skills through internal and client facing activities worldwide. The silo structure offers many career path options and cross silo mobility. That works well if you have the skills and track record of deploying them. Senior management will listen to good ideas but not always responsive. Good place to get the industry tick mark on your CV.
Cons
An extremely complex client facing sales and division structure with many product and strategy overlaps resulting in conflicts of who does/builds/sells what/when and with whom. This can often leave both the clients and employees confused as minions churn about like piranha circling a goat in the Amazon all chasing the same dollar. The sales compensation structure is too complex. It is overlapping often paying out just for coding a record into someone's domain without ever actually selling anything or even leaving the office. Up to 10 sales people can be paid on the same order. Insane but good money for surfing the order logs. Senior management has lost it's sense of what the corporate mission is. They are struggling to redefine the company witness the latest 'cloud' mantra. Much of that is 'me to' versus thought leading. Cloud, mobile and you name it as a service where not invented at IBM. The potential is there to grow but the current hierarchy and competing silo businesses do not promote best practices for optimal corporate development. The cloud business diminishes hardware opportunity, services divisions don't care whose platform they work on, clients are relegated to opportunistic business partners who in turn transfer risk back to IBM whilst taking payment for doing so. There are organizational pieces that clearly don't fit. Notably the Finance Company should be spun off thereby helping relieving the balance sheet of debt while in one fell swoop making the insane 2015 profit target which is a piece of financial engineering having nothing to do with sales growth. It's really just a bank and in fact competes with banks directly. HR practices have reverted to archaic impersonal controls, meaningless reviews, mandatory poor performer rankings and a cheapskate clipping of costs/benefits all the while exporting jobs to low wage and low skill markets. IBM long ago stopped being a people company. It has fallen off the best companies to work for league table. IBM suffers from poor morale and needless productivity loss generated by the constant fear of job loss through 'rebalancing'. I pray for them every night. You should too.