Pros
It's an opportunity to work in a highly matrixed organization. It used to be about working for a company that had a purpose you could believe in... although it's a good bet that isn't the case any longer.
Cons
Too many chiefs, not enough indians: Too many MBAs hired to rank-and-file positions. The company's party line doesn't match with its bottom line: This is reflected in every business decision they make, and in the way they treat their people on the whole. Projects in the planning pipeline don't get useful feedback at the appropriate time, resulting in badly planned and mistimed projects being launched. In theory, the "trains" can be rolled back, but the reality is, once a project is past initial acceptance, the rest of the approval process is just rubberstamping.