Pros
IBM is a great company as a whole. That's the main reason I've stayed for over a year after being hired as an intern. I have gotten some great projects and exposure right out of college. There's also an insane amount of free internal learning and it is highly encouraged and mandatory in some cases to learn new things on the job. Work-life balance is great. I can work from home many days. The benefits are excellent. I have amazing doctors and the actual insurance companies offer many extra resources to IBM employees. 401k matching is also very ideal, I've saved quite a bit in a very short amount of time. There are also other nice perks like being a preferred employer at apartment complexes where I lived. Overall, you're covered if you're at IBM and in truth, they prepare you for a career in- or outside of the company. All of their certifications are transferable skills.
Cons
I still don't have an official title since my projects are all over the place. Unfortunately as an intern hire, I didn't have the flexibility to negotiate my salary or have a say in what position I wanted to be in. As a result, I am extremely underpaid. Also, I was placed in a team full of managers as entry-level, so that means I didn't have the chance to get a real raise. This is an unfortunately situation since I don't think I can get the pay jump I need unless I leave the company and then come back.