Pros
There are many different types of jobs at GM. You can move around relatively easily if you are at lower levels in the organization but it gets harder as you move up the ladder. The people here are generally ok - but - there is still alot of dead weight in the organization as a whole. Some of the best engineers I have worked with have been at GM. Until recently, the benefits were great and very competitive. It's cool to work on cars / trucks - very challenging adn fulfilling when you can see your product on the road.
Cons
GM seems to lack a general plan for future growth. They have made improvements with the UAW but the union still controls much of the play especially in North America. You don't get the feel that the cost cutting initiatives are being done at all levels - execs are still flying company planes when they could fly commercial - still driving company cars and getting gas paid for - great perks - but sends the wrong message to the rest of the organization. Not sure that the other regions of the globe can carry the burden of what has taken place in NA.